My Random Padlet by Fionn

do some random stuff

MagicBudgie — 2016-10-19 09:04:19 UTC

Humans United

fakkle786 — 2017-05-11 13:55:26 UTC

#FREEPALESTINE

azizrahman809 — 2017-05-11 13:55:57 UTC

azizrahman809 — 2017-05-11 13:58:45 UTC

Kobir is a lunn

ure4 dad takes it

azizrahman809 — 2017-05-11 13:59:02 UTC

up the twonker for bants bro

Pls stop this madness

hrwalls03 — 2017-08-10 15:48:44 UTC

Hue Hue Hue

james5dainton — 2017-09-22 01:33:03 UTC

When was this made?

james5dainton — 2017-09-22 01:35:29 UTC

james wat

2017-09-22 01:39:40 UTC

m8 get rit of this

2017-09-22 01:56:40 UTC

i love meme

2017-09-22 01:59:24 UTC

excellent and good they are

CRASH BANDERCOOT

2017-10-04 15:33:07 UTC

Pepe the dancing code frog

2017-10-04 15:34:06 UTC

2017-10-04 15:42:24 UTC

2017-10-04 15:42:26 UTC

2017-10-04 15:42:27 UTC

2017-10-04 15:42:28 UTC

2017-10-04 15:42:41 UTC

DOwnload mE and try to figure out the password :)

titedog33 — 2017-11-19 15:58:48 UTC

http://www.filedropper.com/windowsformsapplicationpotato

garynowiknowthatiwasgayimessedupbecauseimgaygaygaygaygayagyagyagy

2017-12-04 18:01:21 UTC

imygodicantspeakcausesomeoneatemyteeth

2017-12-04 18:02:24 UTC

yourmomisgay23 — 2017-12-04 18:02:47 UTC

your mum gay

JohnWilkesBooth — 2017-12-04 18:03:13 UTC

yourmomisgay23 — 2017-12-04 18:03:17 UTC

me me big boy

JohnWilkesBooth — 2017-12-04 18:04:06 UTC

No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic Table

2017-12-04 18:12:23 UTC

No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic Table

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Atomic
Weight NameSym.M.P.
(°C) B.P.
(°C)Density*
(g/cm³)Earth
crust (%)*Discovery
(Year)Group*Electron
configurationIonization
energy (eV)
1 | | 1.008 | Hydrogen | H | -259 | -253 | 0.09 | 0.14 | 1776 | 1 | 1s¹ | 13.60
2 | | 4.003 | Helium | He | -272 | -269 | 0.18 | | 1895 | 18 | 1s² | 24.59
3 | | 6.941 | Lithium | Li | 180 | 1,347 | 0.53 | | 1817 | 1 | [He] 2s¹ | 5.39
4 | | 9.012 | Beryllium | Be | 1,278 | 2,970 | 1.85 | | 1797 | 2 | [He] 2s² | 9.32
5 | | 10.811 | Boron | B | 2,300 | 2,550 | 2.34 | | 1808 | 13 | [He] 2s² 2p¹ | 8.30
6 | | 12.011 | Carbon | C | 3,500 | 4,827 | 2.26 | 0.09 | ancient | 14 | [He] 2s² 2p² | 11.26
7 | | 14.007 | Nitrogen | N | -210 | -196 | 1.25 | | 1772 | 15 | [He] 2s² 2p³ | 14.53
8 | | 15.999 | Oxygen | O | -218 | -183 | 1.43 | 46.71 | 1774 | 16 | [He] 2s² 2p⁴ | 13.62
9 | | 18.998 | Fluorine | F | -220 | -188 | 1.70 | 0.03 | 1886 | 17 | [He] 2s² 2p⁵ | 17.42
10 | | 20.180 | Neon | Ne | -249 | -246 | 0.90 | | 1898 | 18 | [He] 2s² 2p⁶ | 21.56
11 | | 22.990 | Sodium | Na | 98 | 883 | 0.97 | 2.75 | 1807 | 1 | [Ne] 3s¹ | 5.14
12 | | 24.305 | Magnesium | Mg | 639 | 1,090 | 1.74 | 2.08 | 1755 | 2 | [Ne] 3s² | 7.65
13 | | 26.982 | Aluminum | Al | 660 | 2,467 | 2.70 | 8.07 | 1825 | 13 | [Ne] 3s² 3p¹ | 5.99
14 | | 28.086 | Silicon | Si | 1,410 | 2,355 | 2.33 | 27.69 | 1824 | 14 | [Ne] 3s² 3p² | 8.15
15 | | 30.974 | Phosphorus | P | 44 | 280 | 1.82 | 0.13 | 1669 | 15 | [Ne] 3s² 3p³ | 10.49
16 | | 32.065 | Sulfur | S | 113 | 445 | 2.07 | 0.05 | ancient | 16 | [Ne] 3s² 3p⁴ | 10.36
17 | | 35.453 | Chlorine | Cl | -101 | -35 | 3.21 | 0.05 | 1774 | 17 | [Ne] 3s² 3p⁵ | 12.97
18 | | 39.948 | Argon | Ar | -189 | -186 | 1.78 | | 1894 | 18 | [Ne] 3s² 3p⁶ | 15.76
19 | | 39.098 | Potassium | K | 64 | 774 | 0.86 | 2.58 | 1807 | 1 | [Ar] 4s¹ | 4.34
20 | | 40.078 | Calcium | Ca | 839 | 1,484 | 1.55 | 3.65 | 1808 | 2 | [Ar] 4s² | 6.11
21 | | 44.956 | Scandium | Sc | 1,539 | 2,832 | 2.99 | | 1879 | 3 | [Ar] 3d¹ 4s² | 6.56
22 | | 47.867 | Titanium | Ti | 1,660 | 3,287 | 4.54 | 0.62 | 1791 | 4 | [Ar] 3d² 4s² | 6.83
23 | | 50.942 | Vanadium | V | 1,890 | 3,380 | 6.11 | | 1830 | 5 | [Ar] 3d³ 4s² | 6.75
24 | | 51.996 | Chromium | Cr | 1,857 | 2,672 | 7.19 | 0.04 | 1797 | 6 | [Ar] 3d⁵ 4s¹ | 6.77
25 | | 54.938 | Manganese | Mn | 1,245 | 1,962 | 7.43 | 0.09 | 1774 | 7 | [Ar] 3d⁵ 4s² | 7.43
26 | | 55.845 | Iron | Fe | 1,535 | 2,750 | 7.87 | 5.05 | ancient | 8 | [Ar] 3d⁶ 4s² | 7.90
27 | | 58.933 | Cobalt | Co | 1,495 | 2,870 | 8.90 | | 1735 | 9 | [Ar] 3d⁷ 4s² | 7.88
28 | | 58.693 | Nickel | Ni | 1,453 | 2,732 | 8.90 | 0.02 | 1751 | 10 | [Ar] 3d⁸ 4s² | 7.64
29 | | 63.546 | Copper | Cu | 1,083 | 2,567 | 8.96 | | ancient | 11 | [Ar] 3d¹⁰ 4s¹ | 7.73
30 | | 65.390 | Zinc | Zn | 420 | 907 | 7.13 | | ancient | 12 | [Ar] 3d¹⁰ 4s² | 9.39
31 | | 69.723 | Gallium | Ga | 30 | 2,403 | 5.91 | | 1875 | 13 | [Ar] 3d¹⁰ 4s² 4p¹ | 6.00
32 | | 72.640 | Germanium | Ge | 937 | 2,830 | 5.32 | | 1886 | 14 | [Ar] 3d¹⁰ 4s² 4p² | 7.90
33 | | 74.922 | Arsenic | As | 81 | 613 | 5.72 | | ancient | 15 | [Ar] 3d¹⁰ 4s² 4p³ | 9.79
34 | | 78.960 | Selenium | Se | 217 | 685 | 4.79 | | 1817 | 16 | [Ar] 3d¹⁰ 4s² 4p⁴ | 9.75
35 | | 79.904 | Bromine | Br | -7 | 59 | 3.12 | | 1826 | 17 | [Ar] 3d¹⁰ 4s² 4p⁵ | 11.81
36 | | 83.800 | Krypton | Kr | -157 | -153 | 3.75 | | 1898 | 18 | [Ar] 3d¹⁰ 4s² 4p⁶ | 14.00
37 | | 85.468 | Rubidium | Rb | 39 | 688 | 1.63 | | 1861 | 1 | [Kr] 5s¹ | 4.18
38 | | 87.620 | Strontium | Sr | 769 | 1,384 | 2.54 | | 1790 | 2 | [Kr] 5s² | 5.69
39 | | 88.906 | Yttrium | Y | 1,523 | 3,337 | 4.47 | | 1794 | 3 | [Kr] 4d¹ 5s² | 6.22
40 | | 91.224 | Zirconium | Zr | 1,852 | 4,377 | 6.51 | 0.03 | 1789 | 4 | [Kr] 4d² 5s² | 6.63
41 | | 92.906 | Niobium | Nb | 2,468 | 4,927 | 8.57 | | 1801 | 5 | [Kr] 4d⁴ 5s¹ | 6.76
42 | | 95.940 | Molybdenum | Mo | 2,617 | 4,612 | 10.22 | | 1781 | 6 | [Kr] 4d⁵ 5s¹ | 7.09
43 | * | 98.000 | Technetium | Tc | 2,200 | 4,877 | 11.50 | | 1937 | 7 | [Kr] 4d⁵ 5s² | 7.28
44 | | 101.070 | Ruthenium | Ru | 2,250 | 3,900 | 12.37 | | 1844 | 8 | [Kr] 4d⁷ 5s¹ | 7.36
45 | | 102.906 | Rhodium | Rh | 1,966 | 3,727 | 12.41 | | 1803 | 9 | [Kr] 4d⁸ 5s¹ | 7.46
46 | | 106.420 | Palladium | Pd | 1,552 | 2,927 | 12.02 | | 1803 | 10 | [Kr] 4d¹⁰ | 8.34
47 | | 107.868 | Silver | Ag | 962 | 2,212 | 10.50 | | ancient | 11 | [Kr] 4d¹⁰ 5s¹ | 7.58
48 | | 112.411 | Cadmium | Cd | 321 | 765 | 8.65 | | 1817 | 12 | [Kr] 4d¹⁰ 5s² | 8.99
49 | | 114.818 | Indium | In | 157 | 2,000 | 7.31 | | 1863 | 13 | [Kr] 4d¹⁰ 5s² 5p¹ | 5.79
50 | | 118.710 | Tin | Sn | 232 | 2,270 | 7.31 | | ancient | 14 | [Kr] 4d¹⁰ 5s² 5p² | 7.34
51 | | 121.760 | Antimony | Sb | 630 | 1,750 | 6.68 | | ancient | 15 | [Kr] 4d¹⁰ 5s² 5p³ | 8.61
52 | | 127.600 | Tellurium | Te | 449 | 990 | 6.24 | | 1783 | 16 | [Kr] 4d¹⁰ 5s² 5p⁴ | 9.01
53 | | 126.905 | Iodine | I | 114 | 184 | 4.93 | | 1811 | 17 | [Kr] 4d¹⁰ 5s² 5p⁵ | 10.45
54 | | 131.293 | Xenon | Xe | -112 | -108 | 5.90 | | 1898 | 18 | [Kr] 4d¹⁰ 5s² 5p⁶ | 12.13
55 | | 132.906 | Cesium | Cs | 29 | 678 | 1.87 | | 1860 | 1 | [Xe] 6s¹ | 3.89
56 | | 137.327 | Barium | Ba | 725 | 1,140 | 3.59 | 0.05 | 1808 | 2 | [Xe] 6s² | 5.21
57 | | 138.906 | Lanthanum | La | 920 | 3,469 | 6.15 | | 1839 | 3 | [Xe] 5d¹ 6s² | 5.58
58 | | 140.116 | Cerium | Ce | 795 | 3,257 | 6.77 | | 1803 | 101 | [Xe] 4f¹ 5d¹ 6s² | 5.54
59 | | 140.908 | Praseodymium | Pr | 935 | 3,127 | 6.77 | | 1885 | 101 | [Xe] 4f³ 6s² | 5.47
60 | | 144.240 | Neodymium | Nd | 1,010 | 3,127 | 7.01 | | 1885 | 101 | [Xe] 4f⁴ 6s² | 5.53
61 | * | 145.000 | Promethium | Pm | 1,100 | 3,000 | 7.30 | | 1945 | 101 | [Xe] 4f⁵ 6s² | 5.58
62 | | 150.360 | Samarium | Sm | 1,072 | 1,900 | 7.52 | | 1879 | 101 | [Xe] 4f⁶ 6s² | 5.64
63 | | 151.964 | Europium | Eu | 822 | 1,597 | 5.24 | | 1901 | 101 | [Xe] 4f⁷ 6s² | 5.67
64 | | 157.250 | Gadolinium | Gd | 1,311 | 3,233 | 7.90 | | 1880 | 101 | [Xe] 4f⁷ 5d¹ 6s² | 6.15
65 | | 158.925 | Terbium | Tb | 1,360 | 3,041 | 8.23 | | 1843 | 101 | [Xe] 4f⁹ 6s² | 5.86
66 | | 162.500 | Dysprosium | Dy | 1,412 | 2,562 | 8.55 | | 1886 | 101 | [Xe] 4f¹⁰ 6s² | 5.94
67 | | 164.930 | Holmium | Ho | 1,470 | 2,720 | 8.80 | | 1867 | 101 | [Xe] 4f¹¹ 6s² | 6.02
68 | | 167.259 | Erbium | Er | 1,522 | 2,510 | 9.07 | | 1842 | 101 | [Xe] 4f¹² 6s² | 6.11
69 | | 168.934 | Thulium | Tm | 1,545 | 1,727 | 9.32 | | 1879 | 101 | [Xe] 4f¹³ 6s² | 6.18
70 | | 173.040 | Ytterbium | Yb | 824 | 1,466 | 6.90 | | 1878 | 101 | [Xe] 4f¹⁴ 6s² | 6.25
71 | | 174.967 | Lutetium | Lu | 1,656 | 3,315 | 9.84 | | 1907 | 101 | [Xe] 4f¹⁴ 5d¹ 6s² | 5.43
72 | | 178.490 | Hafnium | Hf | 2,150 | 5,400 | 13.31 | | 1923 | 4 | [Xe] 4f¹⁴ 5d² 6s² | 6.83
73 | | 180.948 | Tantalum | Ta | 2,996 | 5,425 | 16.65 | | 1802 | 5 | [Xe] 4f¹⁴ 5d³ 6s² | 7.55
74 | | 183.840 | Tungsten | W | 3,410 | 5,660 | 19.35 | | 1783 | 6 | [Xe] 4f¹⁴ 5d⁴ 6s² | 7.86
75 | | 186.207 | Rhenium | Re | 3,180 | 5,627 | 21.04 | | 1925 | 7 | [Xe] 4f¹⁴ 5d⁵ 6s² | 7.83
76 | | 190.230 | Osmium | Os | 3,045 | 5,027 | 22.60 | | 1803 | 8 | [Xe] 4f¹⁴ 5d⁶ 6s² | 8.44
77 | | 192.217 | Iridium | Ir | 2,410 | 4,527 | 22.40 | | 1803 | 9 | [Xe] 4f¹⁴ 5d⁷ 6s² | 8.97
78 | | 195.078 | Platinum | Pt | 1,772 | 3,827 | 21.45 | | 1735 | 10 | [Xe] 4f¹⁴ 5d⁹ 6s¹ | 8.96
79 | | 196.967 | Gold | Au | 1,064 | 2,807 | 19.32 | | ancient | 11 | [Xe] 4f¹⁴ 5d¹⁰ 6s¹ | 9.23
80 | | 200.590 | Mercury | Hg | -39 | 357 | 13.55 | | ancient | 12 | [Xe] 4f¹⁴ 5d¹⁰ 6s² | 10.44
81 | | 204.383 | Thallium | Tl | 303 | 1,457 | 11.85 | | 1861 | 13 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹ | 6.11
82 | | 207.200 | Lead | Pb | 327 | 1,740 | 11.35 | | ancient | 14 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p² | 7.42
83 | | 208.980 | Bismuth | Bi | 271 | 1,560 | 9.75 | | ancient | 15 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³ | 7.29
84 | * | 209.000 | Polonium | Po | 254 | 962 | 9.30 | | 1898 | 16 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁴ | 8.42
85 | * | 210.000 | Astatine | At | 302 | 337 | 0.00 | | 1940 | 17 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵ | 9.30
86 | * | 222.000 | Radon | Rn | -71 | -62 | 9.73 | | 1900 | 18 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁶ | 10.75
87 | * | 223.000 | Francium | Fr | 27 | 677 | 0.00 | | 1939 | 1 | [Rn] 7s¹ | 4.07
88 | * | 226.000 | Radium | Ra | 700 | 1,737 | 5.50 | | 1898 | 2 | [Rn] 7s² | 5.28
89 | * | 227.000 | Actinium | Ac | 1,050 | 3,200 | 10.07 | | 1899 | 3 | [Rn] 6d¹ 7s² | 5.17
90 | | 232.038 | Thorium | Th | 1,750 | 4,790 | 11.72 | | 1829 | 102 | [Rn] 6d² 7s² | 6.31
91 | | 231.036 | Protactinium | Pa | 1,568 | 0 | 15.40 | | 1913 | 102 | [Rn] 5f² 6d¹ 7s² | 5.89
92 | | 238.029 | Uranium | U | 1,132 | 3,818 | 18.95 | | 1789 | 102 | [Rn] 5f³ 6d¹ 7s² | 6.19
93 | * | 237.000 | Neptunium | Np | 640 | 3,902 | 20.20 | | 1940 | 102 | [Rn] 5f⁴ 6d¹ 7s² | 6.27
94 | * | 244.000 | Plutonium | Pu | 640 | 3,235 | 19.84 | | 1940 | 102 | [Rn] 5f⁶ 7s² | 6.03
95 | * | 243.000 | Americium | Am | 994 | 2,607 | 13.67 | | 1944 | 102 | [Rn] 5f⁷ 7s² | 5.97
96 | * | 247.000 | Curium | Cm | 1,340 | 0 | 13.50 | | 1944 | 102 | | 5.99
97 | * | 247.000 | Berkelium | Bk | 986 | 0 | 14.78 | | 1949 | 102 | | 6.20
98 | * | 251.000 | Californium | Cf | 900 | 0 | 15.10 | | 1950 | 102 | | 6.28
99 | * | 252.000 | Einsteinium | Es | 860 | 0 | 0.00 | | 1952 | 102 | | 6.42
100 | * | 257.000 | Fermium | Fm | 1,527 | 0 | 0.00 | | 1952 | 102 | | 6.50
101 | * | 258.000 | Mendelevium | Md | 0 | 0 | 0.00 | | 1955 | 102 | | 6.58
102 | * | 259.000 | Nobelium | No | 827 | 0 | 0.00 | | 1958 | 102 | | 6.65
103 | * | 262.000 | Lawrencium | Lr | 1,627 | 0 | 0.00 | | 1961 | 102 | | 4.90
104 | * | 261.000 | Rutherfordium | Rf | 0 | 0 | 0.00 | | 1964 | 4 | | 0.00
105 | * | 262.000 | Dubnium | Db | 0 | 0 | 0.00 | | 1967 | 5 | | 0.00
106 | * | 266.000 | Seaborgium | Sg | 0 | 0 | 0.00 | | 1974 | 6 | | 0.00
107 | * | 264.000 | Bohrium | Bh | 0 | 0 | 0.00 | | 1981 | 7 | | 0.00
108 | * | 277.000 | Hassium | Hs | 0 | 0 | 0.00 | | 1984 | 8 | | 0.00
109 | * | 268.000 | Meitnerium | Mt | 0 | 0 | 0.00 | | 1982 | 9 | | 0.00
No.
Atomic
Weight NameSym.M.P.
(°C) B.P.
(°C)Density*
(g/cm³)Earth
crust (%)*Discovery
(Year)Group*Electron
configurationIonization
energy (eV)

↑ Top of table

Notes:
• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C.
• Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).
• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.
• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.

Abbreviations and Definitions:

No. - Atomic Number
M.P. - melting point
B.P. - boiling point

Atomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.

Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, ¹²C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.

Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, ¹²C and ¹³C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.

Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.

Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.

Energy levels and sublevelsPrincipal energy level
(Quantum number: n) | Sublevels available
(Quantum number: l)
1
2
3
4
5
6 | 1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f 5g
6s 6p 6d 6f 6g 6h

Ionization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.

Other resources related to the Periodic TableNo.
Atomic
Weight NameSym.M.P.
(°C) B.P.
(°C)Density*
(g/cm³)Earth
crust (%)*Discovery
(Year)Group*Electron
configurationIonization
energy (eV)
1 | | 1.008 | Hydrogen | H | -259 | -253 | 0.09 | 0.14 | 1776 | 1 | 1s¹ | 13.60
2 | | 4.003 | Helium | He | -272 | -269 | 0.18 | | 1895 | 18 | 1s² | 24.59
3 | | 6.941 | Lithium | Li | 180 | 1,347 | 0.53 | | 1817 | 1 | [He] 2s¹ | 5.39
4 | | 9.012 | Beryllium | Be | 1,278 | 2,970 | 1.85 | | 1797 | 2 | [He] 2s² | 9.32
5 | | 10.811 | Boron | B | 2,300 | 2,550 | 2.34 | | 1808 | 13 | [He] 2s² 2p¹ | 8.30
6 | | 12.011 | Carbon | C | 3,500 | 4,827 | 2.26 | 0.09 | ancient | 14 | [He] 2s² 2p² | 11.26
7 | | 14.007 | Nitrogen | N | -210 | -196 | 1.25 | | 1772 | 15 | [He] 2s² 2p³ | 14.53
8 | | 15.999 | Oxygen | O | -218 | -183 | 1.43 | 46.71 | 1774 | 16 | [He] 2s² 2p⁴ | 13.62
9 | | 18.998 | Fluorine | F | -220 | -188 | 1.70 | 0.03 | 1886 | 17 | [He] 2s² 2p⁵ | 17.42
10 | | 20.180 | Neon | Ne | -249 | -246 | 0.90 | | 1898 | 18 | [He] 2s² 2p⁶ | 21.56
11 | | 22.990 | Sodium | Na | 98 | 883 | 0.97 | 2.75 | 1807 | 1 | [Ne] 3s¹ | 5.14
12 | | 24.305 | Magnesium | Mg | 639 | 1,090 | 1.74 | 2.08 | 1755 | 2 | [Ne] 3s² | 7.65
13 | | 26.982 | Aluminum | Al | 660 | 2,467 | 2.70 | 8.07 | 1825 | 13 | [Ne] 3s² 3p¹ | 5.99
14 | | 28.086 | Silicon | Si | 1,410 | 2,355 | 2.33 | 27.69 | 1824 | 14 | [Ne] 3s² 3p² | 8.15
15 | | 30.974 | Phosphorus | P | 44 | 280 | 1.82 | 0.13 | 1669 | 15 | [Ne] 3s² 3p³ | 10.49
16 | | 32.065 | Sulfur | S | 113 | 445 | 2.07 | 0.05 | ancient | 16 | [Ne] 3s² 3p⁴ | 10.36
17 | | 35.453 | Chlorine | Cl | -101 | -35 | 3.21 | 0.05 | 1774 | 17 | [Ne] 3s² 3p⁵ | 12.97
18 | | 39.948 | Argon | Ar | -189 | -186 | 1.78 | | 1894 | 18 | [Ne] 3s² 3p⁶ | 15.76
19 | | 39.098 | Potassium | K | 64 | 774 | 0.86 | 2.58 | 1807 | 1 | [Ar] 4s¹ | 4.34
20 | | 40.078 | Calcium | Ca | 839 | 1,484 | 1.55 | 3.65 | 1808 | 2 | [Ar] 4s² | 6.11
21 | | 44.956 | Scandium | Sc | 1,539 | 2,832 | 2.99 | | 1879 | 3 | [Ar] 3d¹ 4s² | 6.56
22 | | 47.867 | Titanium | Ti | 1,660 | 3,287 | 4.54 | 0.62 | 1791 | 4 | [Ar] 3d² 4s² | 6.83
23 | | 50.942 | Vanadium | V | 1,890 | 3,380 | 6.11 | | 1830 | 5 | [Ar] 3d³ 4s² | 6.75
24 | | 51.996 | Chromium | Cr | 1,857 | 2,672 | 7.19 | 0.04 | 1797 | 6 | [Ar] 3d⁵ 4s¹ | 6.77
25 | | 54.938 | Manganese | Mn | 1,245 | 1,962 | 7.43 | 0.09 | 1774 | 7 | [Ar] 3d⁵ 4s² | 7.43
26 | | 55.845 | Iron | Fe | 1,535 | 2,750 | 7.87 | 5.05 | ancient | 8 | [Ar] 3d⁶ 4s² | 7.90
27 | | 58.933 | Cobalt | Co | 1,495 | 2,870 | 8.90 | | 1735 | 9 | [Ar] 3d⁷ 4s² | 7.88
28 | | 58.693 | Nickel | Ni | 1,453 | 2,732 | 8.90 | 0.02 | 1751 | 10 | [Ar] 3d⁸ 4s² | 7.64
29 | | 63.546 | Copper | Cu | 1,083 | 2,567 | 8.96 | | ancient | 11 | [Ar] 3d¹⁰ 4s¹ | 7.73
30 | | 65.390 | Zinc | Zn | 420 | 907 | 7.13 | | ancient | 12 | [Ar] 3d¹⁰ 4s² | 9.39
31 | | 69.723 | Gallium | Ga | 30 | 2,403 | 5.91 | | 1875 | 13 | [Ar] 3d¹⁰ 4s² 4p¹ | 6.00
32 | | 72.640 | Germanium | Ge | 937 | 2,830 | 5.32 | | 1886 | 14 | [Ar] 3d¹⁰ 4s² 4p² | 7.90
33 | | 74.922 | Arsenic | As | 81 | 613 | 5.72 | | ancient | 15 | [Ar] 3d¹⁰ 4s² 4p³ | 9.79
34 | | 78.960 | Selenium | Se | 217 | 685 | 4.79 | | 1817 | 16 | [Ar] 3d¹⁰ 4s² 4p⁴ | 9.75
35 | | 79.904 | Bromine | Br | -7 | 59 | 3.12 | | 1826 | 17 | [Ar] 3d¹⁰ 4s² 4p⁵ | 11.81
36 | | 83.800 | Krypton | Kr | -157 | -153 | 3.75 | | 1898 | 18 | [Ar] 3d¹⁰ 4s² 4p⁶ | 14.00
37 | | 85.468 | Rubidium | Rb | 39 | 688 | 1.63 | | 1861 | 1 | [Kr] 5s¹ | 4.18
38 | | 87.620 | Strontium | Sr | 769 | 1,384 | 2.54 | | 1790 | 2 | [Kr] 5s² | 5.69
39 | | 88.906 | Yttrium | Y | 1,523 | 3,337 | 4.47 | | 1794 | 3 | [Kr] 4d¹ 5s² | 6.22
40 | | 91.224 | Zirconium | Zr | 1,852 | 4,377 | 6.51 | 0.03 | 1789 | 4 | [Kr] 4d² 5s² | 6.63
41 | | 92.906 | Niobium | Nb | 2,468 | 4,927 | 8.57 | | 1801 | 5 | [Kr] 4d⁴ 5s¹ | 6.76
42 | | 95.940 | Molybdenum | Mo | 2,617 | 4,612 | 10.22 | | 1781 | 6 | [Kr] 4d⁵ 5s¹ | 7.09
43 | * | 98.000 | Technetium | Tc | 2,200 | 4,877 | 11.50 | | 1937 | 7 | [Kr] 4d⁵ 5s² | 7.28
44 | | 101.070 | Ruthenium | Ru | 2,250 | 3,900 | 12.37 | | 1844 | 8 | [Kr] 4d⁷ 5s¹ | 7.36
45 | | 102.906 | Rhodium | Rh | 1,966 | 3,727 | 12.41 | | 1803 | 9 | [Kr] 4d⁸ 5s¹ | 7.46
46 | | 106.420 | Palladium | Pd | 1,552 | 2,927 | 12.02 | | 1803 | 10 | [Kr] 4d¹⁰ | 8.34
47 | | 107.868 | Silver | Ag | 962 | 2,212 | 10.50 | | ancient | 11 | [Kr] 4d¹⁰ 5s¹ | 7.58
48 | | 112.411 | Cadmium | Cd | 321 | 765 | 8.65 | | 1817 | 12 | [Kr] 4d¹⁰ 5s² | 8.99
49 | | 114.818 | Indium | In | 157 | 2,000 | 7.31 | | 1863 | 13 | [Kr] 4d¹⁰ 5s² 5p¹ | 5.79
50 | | 118.710 | Tin | Sn | 232 | 2,270 | 7.31 | | ancient | 14 | [Kr] 4d¹⁰ 5s² 5p² | 7.34
51 | | 121.760 | Antimony | Sb | 630 | 1,750 | 6.68 | | ancient | 15 | [Kr] 4d¹⁰ 5s² 5p³ | 8.61
52 | | 127.600 | Tellurium | Te | 449 | 990 | 6.24 | | 1783 | 16 | [Kr] 4d¹⁰ 5s² 5p⁴ | 9.01
53 | | 126.905 | Iodine | I | 114 | 184 | 4.93 | | 1811 | 17 | [Kr] 4d¹⁰ 5s² 5p⁵ | 10.45
54 | | 131.293 | Xenon | Xe | -112 | -108 | 5.90 | | 1898 | 18 | [Kr] 4d¹⁰ 5s² 5p⁶ | 12.13
55 | | 132.906 | Cesium | Cs | 29 | 678 | 1.87 | | 1860 | 1 | [Xe] 6s¹ | 3.89
56 | | 137.327 | Barium | Ba | 725 | 1,140 | 3.59 | 0.05 | 1808 | 2 | [Xe] 6s² | 5.21
57 | | 138.906 | Lanthanum | La | 920 | 3,469 | 6.15 | | 1839 | 3 | [Xe] 5d¹ 6s² | 5.58
58 | | 140.116 | Cerium | Ce | 795 | 3,257 | 6.77 | | 1803 | 101 | [Xe] 4f¹ 5d¹ 6s² | 5.54
59 | | 140.908 | Praseodymium | Pr | 935 | 3,127 | 6.77 | | 1885 | 101 | [Xe] 4f³ 6s² | 5.47
60 | | 144.240 | Neodymium | Nd | 1,010 | 3,127 | 7.01 | | 1885 | 101 | [Xe] 4f⁴ 6s² | 5.53
61 | * | 145.000 | Promethium | Pm | 1,100 | 3,000 | 7.30 | | 1945 | 101 | [Xe] 4f⁵ 6s² | 5.58
62 | | 150.360 | Samarium | Sm | 1,072 | 1,900 | 7.52 | | 1879 | 101 | [Xe] 4f⁶ 6s² | 5.64
63 | | 151.964 | Europium | Eu | 822 | 1,597 | 5.24 | | 1901 | 101 | [Xe] 4f⁷ 6s² | 5.67
64 | | 157.250 | Gadolinium | Gd | 1,311 | 3,233 | 7.90 | | 1880 | 101 | [Xe] 4f⁷ 5d¹ 6s² | 6.15
65 | | 158.925 | Terbium | Tb | 1,360 | 3,041 | 8.23 | | 1843 | 101 | [Xe] 4f⁹ 6s² | 5.86
66 | | 162.500 | Dysprosium | Dy | 1,412 | 2,562 | 8.55 | | 1886 | 101 | [Xe] 4f¹⁰ 6s² | 5.94
67 | | 164.930 | Holmium | Ho | 1,470 | 2,720 | 8.80 | | 1867 | 101 | [Xe] 4f¹¹ 6s² | 6.02
68 | | 167.259 | Erbium | Er | 1,522 | 2,510 | 9.07 | | 1842 | 101 | [Xe] 4f¹² 6s² | 6.11
69 | | 168.934 | Thulium | Tm | 1,545 | 1,727 | 9.32 | | 1879 | 101 | [Xe] 4f¹³ 6s² | 6.18
70 | | 173.040 | Ytterbium | Yb | 824 | 1,466 | 6.90 | | 1878 | 101 | [Xe] 4f¹⁴ 6s² | 6.25
71 | | 174.967 | Lutetium | Lu | 1,656 | 3,315 | 9.84 | | 1907 | 101 | [Xe] 4f¹⁴ 5d¹ 6s² | 5.43
72 | | 178.490 | Hafnium | Hf | 2,150 | 5,400 | 13.31 | | 1923 | 4 | [Xe] 4f¹⁴ 5d² 6s² | 6.83
73 | | 180.948 | Tantalum | Ta | 2,996 | 5,425 | 16.65 | | 1802 | 5 | [Xe] 4f¹⁴ 5d³ 6s² | 7.55
74 | | 183.840 | Tungsten | W | 3,410 | 5,660 | 19.35 | | 1783 | 6 | [Xe] 4f¹⁴ 5d⁴ 6s² | 7.86
75 | | 186.207 | Rhenium | Re | 3,180 | 5,627 | 21.04 | | 1925 | 7 | [Xe] 4f¹⁴ 5d⁵ 6s² | 7.83
76 | | 190.230 | Osmium | Os | 3,045 | 5,027 | 22.60 | | 1803 | 8 | [Xe] 4f¹⁴ 5d⁶ 6s² | 8.44
77 | | 192.217 | Iridium | Ir | 2,410 | 4,527 | 22.40 | | 1803 | 9 | [Xe] 4f¹⁴ 5d⁷ 6s² | 8.97
78 | | 195.078 | Platinum | Pt | 1,772 | 3,827 | 21.45 | | 1735 | 10 | [Xe] 4f¹⁴ 5d⁹ 6s¹ | 8.96
79 | | 196.967 | Gold | Au | 1,064 | 2,807 | 19.32 | | ancient | 11 | [Xe] 4f¹⁴ 5d¹⁰ 6s¹ | 9.23
80 | | 200.590 | Mercury | Hg | -39 | 357 | 13.55 | | ancient | 12 | [Xe] 4f¹⁴ 5d¹⁰ 6s² | 10.44
81 | | 204.383 | Thallium | Tl | 303 | 1,457 | 11.85 | | 1861 | 13 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹ | 6.11
82 | | 207.200 | Lead | Pb | 327 | 1,740 | 11.35 | | ancient | 14 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p² | 7.42
83 | | 208.980 | Bismuth | Bi | 271 | 1,560 | 9.75 | | ancient | 15 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³ | 7.29
84 | * | 209.000 | Polonium | Po | 254 | 962 | 9.30 | | 1898 | 16 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁴ | 8.42
85 | * | 210.000 | Astatine | At | 302 | 337 | 0.00 | | 1940 | 17 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵ | 9.30
86 | * | 222.000 | Radon | Rn | -71 | -62 | 9.73 | | 1900 | 18 | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁶ | 10.75
87 | * | 223.000 | Francium | Fr | 27 | 677 | 0.00 | | 1939 | 1 | [Rn] 7s¹ | 4.07
88 | * | 226.000 | Radium | Ra | 700 | 1,737 | 5.50 | | 1898 | 2 | [Rn] 7s² | 5.28
89 | * | 227.000 | Actinium | Ac | 1,050 | 3,200 | 10.07 | | 1899 | 3 | [Rn] 6d¹ 7s² | 5.17
90 | | 232.038 | Thorium | Th | 1,750 | 4,790 | 11.72 | | 1829 | 102 | [Rn] 6d² 7s² | 6.31
91 | | 231.036 | Protactinium | Pa | 1,568 | 0 | 15.40 | | 1913 | 102 | [Rn] 5f² 6d¹ 7s² | 5.89
92 | | 238.029 | Uranium | U | 1,132 | 3,818 | 18.95 | | 1789 | 102 | [Rn] 5f³ 6d¹ 7s² | 6.19
93 | * | 237.000 | Neptunium | Np | 640 | 3,902 | 20.20 | | 1940 | 102 | [Rn] 5f⁴ 6d¹ 7s² | 6.27
94 | * | 244.000 | Plutonium | Pu | 640 | 3,235 | 19.84 | | 1940 | 102 | [Rn] 5f⁶ 7s² | 6.03
95 | * | 243.000 | Americium | Am | 994 | 2,607 | 13.67 | | 1944 | 102 | [Rn] 5f⁷ 7s² | 5.97
96 | * | 247.000 | Curium | Cm | 1,340 | 0 | 13.50 | | 1944 | 102 | | 5.99
97 | * | 247.000 | Berkelium | Bk | 986 | 0 | 14.78 | | 1949 | 102 | | 6.20
98 | * | 251.000 | Californium | Cf | 900 | 0 | 15.10 | | 1950 | 102 | | 6.28
99 | * | 252.000 | Einsteinium | Es | 860 | 0 | 0.00 | | 1952 | 102 | | 6.42
100 | * | 257.000 | Fermium | Fm | 1,527 | 0 | 0.00 | | 1952 | 102 | | 6.50
101 | * | 258.000 | Mendelevium | Md | 0 | 0 | 0.00 | | 1955 | 102 | | 6.58
102 | * | 259.000 | Nobelium | No | 827 | 0 | 0.00 | | 1958 | 102 | | 6.65
103 | * | 262.000 | Lawrencium | Lr | 1,627 | 0 | 0.00 | | 1961 | 102 | | 4.90
104 | * | 261.000 | Rutherfordium | Rf | 0 | 0 | 0.00 | | 1964 | 4 | | 0.00
105 | * | 262.000 | Dubnium | Db | 0 | 0 | 0.00 | | 1967 | 5 | | 0.00
106 | * | 266.000 | Seaborgium | Sg | 0 | 0 | 0.00 | | 1974 | 6 | | 0.00
107 | * | 264.000 | Bohrium | Bh | 0 | 0 | 0.00 | | 1981 | 7 | | 0.00
108 | * | 277.000 | Hassium | Hs | 0 | 0 | 0.00 | | 1984 | 8 | | 0.00
109 | * | 268.000 | Meitnerium | Mt | 0 | 0 | 0.00 | | 1982 | 9 | | 0.00
No.
Atomic
Weight NameSym.M.P.
(°C) B.P.
(°C)Density*
(g/cm³)Earth
crust (%)*Discovery
(Year)Group*Electron
configurationIonization
energy (eV)

↑ Top of table

Abbreviations and Definitions:

No. - Atomic Number
M.P. - melting point
B.P. - boiling point

Atomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.

Energy levels and sublevelsPrincipal energy level
(Quantum number: n) | Sublevels available
(Quantum number: l)
1
2
3
4
5
6 | 1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f 5g
6s 6p 6d 6f 6g 6h

↑ Top of table

Abbreviations and Definitions:

No. - Atomic Number
M.P. - melting point
B.P. - boiling point

Atomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.

Energy levels and sublevelsPrincipal energy level
(Quantum number: n) | Sublevels available
(Quantum number: l)
1
2
3
4
5
6 | 1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f 5g
6s 6p 6d 6f 6g 6h

↑ Top of table

Abbreviations and Definitions:

No. - Atomic Number
M.P. - melting point
B.P. - boiling point

Atomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.

Energy levels and sublevelsPrincipal energy level
(Quantum number: n) | Sublevels available
(Quantum number: l)
1
2
3
4
5
6 | 1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f 5g
6s 6p 6d 6f 6g 6h

Other resources related to the Periodic Table

yourmomisgay23 — 2017-12-04 18:34:02 UTC

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No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic TableNo. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)1 1.008 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.602 4.003 Helium He -272 -269 0.18 1895 18 1s2 24.593 6.941 Lithium Li 180 1,347 0.53 1817 1 [He] 2s1 5.394 9.012 Beryllium Be 1,278 2,970 1.85 1797 2 [He] 2s2 9.325 10.811 Boron B 2,300 2,550 2.34 1808 13 [He] 2s2 2p1 8.306 12.011 Carbon C 3,500 4,827 2.26 0.09 ancient 14 [He] 2s2 2p2 11.267 14.007 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.538 15.999 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.629 18.998 Fluorine F -220 -188 1.70 0.03 1886 17 [He] 2s2 2p5 17.4210 20.180 Neon Ne -249 -246 0.90 1898 18 [He] 2s2 2p6 21.5611 22.990 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1412 24.305 Magnesium Mg 639 1,090 1.74 2.08 1755 2 [Ne] 3s2 7.6513 26.982 Aluminum Al 660 2,467 2.70 8.07 1825 13 [Ne] 3s2 3p1 5.9914 28.086 Silicon Si 1,410 2,355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1515 30.974 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4916 32.065 Sulfur S 113 445 2.07 0.05 ancient 16 [Ne] 3s2 3p4 10.3617 35.453 Chlorine Cl -101 -35 3.21 0.05 1774 17 [Ne] 3s2 3p5 12.9718 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7619 39.098 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3420 40.078 Calcium Ca 839 1,484 1.55 3.65 1808 2 [Ar] 4s2 6.1121 44.956 Scandium Sc 1,539 2,832 2.99 1879 3 [Ar] 3d1 4s2 6.5622 47.867 Titanium Ti 1,660 3,287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8323 50.942 Vanadium V 1,890 3,380 6.11 1830 5 [Ar] 3d3 4s2 6.7524 51.996 Chromium Cr 1,857 2,672 7.19 0.04 1797 6 [Ar] 3d5 4s1 6.7725 54.938 Manganese Mn 1,245 1,962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.4326 55.845 Iron Fe 1,535 2,750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9027 58.933 Cobalt Co 1,495 2,870 8.90 1735 9 [Ar] 3d7 4s2 7.8828 58.693 Nickel Ni 1,453 2,732 8.90 0.02 1751 10 [Ar] 3d8 4s2 7.6429 63.546 Copper Cu 1,083 2,567 8.96 ancient 11 [Ar] 3d10 4s1 7.7330 65.390 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3931 69.723 Gallium Ga 30 2,403 5.91 1875 13 [Ar] 3d10 4s2 4p1 6.0032 72.640 Germanium Ge 937 2,830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.9033 74.922 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7934 78.960 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7535 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8136 83.800 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 14.0037 85.468 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1838 87.620 Strontium Sr 769 1,384 2.54 1790 2 [Kr] 5s2 5.6939 88.906 Yttrium Y 1,523 3,337 4.47 1794 3 [Kr] 4d1 5s2 6.2240 91.224 Zirconium Zr 1,852 4,377 6.51 0.03 1789 4 [Kr] 4d2 5s2 6.6341 92.906 Niobium Nb 2,468 4,927 8.57 1801 5 [Kr] 4d4 5s1 6.7642 95.940 Molybdenum Mo 2,617 4,612 10.22 1781 6 [Kr] 4d5 5s1 7.0943 * 98.000 Technetium Tc 2,200 4,877 11.50 1937 7 [Kr] 4d5 5s2 7.2844 101.070 Ruthenium Ru 2,250 3,900 12.37 1844 8 [Kr] 4d7 5s1 7.3645 102.906 Rhodium Rh 1,966 3,727 12.41 1803 9 [Kr] 4d8 5s1 7.4646 106.420 Palladium Pd 1,552 2,927 12.02 1803 10 [Kr] 4d10 8.3447 107.868 Silver Ag 962 2,212 10.50 ancient 11 [Kr] 4d10 5s1 7.5848 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9949 114.818 Indium In 157 2,000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7950 118.710 Tin Sn 232 2,270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3451 121.760 Antimony Sb 630 1,750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6152 127.600 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0153 126.905 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4554 131.293 Xenon Xe -112 -108 5.90 1898 18 [Kr] 4d10 5s2 5p6 12.1355 132.906 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8956 137.327 Barium Ba 725 1,140 3.59 0.05 1808 2 [Xe] 6s2 5.2157 138.906 Lanthanum La 920 3,469 6.15 1839 3 [Xe] 5d1 6s2 5.5858 140.116 Cerium Ce 795 3,257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5459 140.908 Praseodymium Pr 935 3,127 6.77 1885 101 [Xe] 4f3 6s2 5.4760 144.240 Neodymium Nd 1,010 3,127 7.01 1885 101 [Xe] 4f4 6s2 5.5361 * 145.000 Promethium Pm 1,100 3,000 7.30 1945 101 [Xe] 4f5 6s2 5.5862 150.360 Samarium Sm 1,072 1,900 7.52 1879 101 [Xe] 4f6 6s2 5.6463 151.964 Europium Eu 822 1,597 5.24 1901 101 [Xe] 4f7 6s2 5.6764 157.250 Gadolinium Gd 1,311 3,233 7.90 1880 101 [Xe] 4f7 5d1 6s2 6.1565 158.925 Terbium Tb 1,360 3,041 8.23 1843 101 [Xe] 4f9 6s2 5.8666 162.500 Dysprosium Dy 1,412 2,562 8.55 1886 101 [Xe] 4f10 6s2 5.9467 164.930 Holmium Ho 1,470 2,720 8.80 1867 101 [Xe] 4f11 6s2 6.0268 167.259 Erbium Er 1,522 2,510 9.07 1842 101 [Xe] 4f12 6s2 6.1169 168.934 Thulium Tm 1,545 1,727 9.32 1879 101 [Xe] 4f13 6s2 6.1870 173.040 Ytterbium Yb 824 1,466 6.90 1878 101 [Xe] 4f14 6s2 6.2571 174.967 Lutetium Lu 1,656 3,315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4372 178.490 Hafnium Hf 2,150 5,400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8373 180.948 Tantalum Ta 2,996 5,425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5574 183.840 Tungsten W 3,410 5,660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.8675 186.207 Rhenium Re 3,180 5,627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8376 190.230 Osmium Os 3,045 5,027 22.60 1803 8 [Xe] 4f14 5d6 6s2 8.4477 192.217 Iridium Ir 2,410 4,527 22.40 1803 9 [Xe] 4f14 5d7 6s2 8.9778 195.078 Platinum Pt 1,772 3,827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9679 196.967 Gold Au 1,064 2,807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2380 200.590 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4481 204.383 Thallium Tl 303 1,457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1182 207.200 Lead Pb 327 1,740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4283 208.980 Bismuth Bi 271 1,560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2984 * 209.000 Polonium Po 254 962 9.30 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.4285 * 210.000 Astatine At 302 337 0.00 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3086 * 222.000 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7587 * 223.000 Francium Fr 27 677 0.00 1939 1 [Rn] 7s1 4.0788 * 226.000 Radium Ra 700 1,737 5.50 1898 2 [Rn] 7s2 5.2889 * 227.000 Actinium Ac 1,050 3,200 10.07 1899 3 [Rn] 6d1 7s2 5.1790 232.038 Thorium Th 1,750 4,790 11.72 1829 102 [Rn] 6d2 7s2 6.3191 231.036 Protactinium Pa 1,568 0 15.40 1913 102 [Rn] 5f2 6d1 7s2 5.8992 238.029 Uranium U 1,132 3,818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1993 * 237.000 Neptunium Np 640 3,902 20.20 1940 102 [Rn] 5f4 6d1 7s2 6.2794 * 244.000 Plutonium Pu 640 3,235 19.84 1940 102 [Rn] 5f6 7s2 6.0395 * 243.000 Americium Am 994 2,607 13.67 1944 102 [Rn] 5f7 7s2 5.9796 * 247.000 Curium Cm 1,340 0 13.50 1944 102 5.9997 * 247.000 Berkelium Bk 986 0 14.78 1949 102 6.2098 * 251.000 Californium Cf 900 0 15.10 1950 102 6.2899 * 252.000 Einsteinium Es 860 0 0.00 1952 102 6.42100 * 257.000 Fermium Fm 1,527 0 0.00 1952 102 6.50101 * 258.000 Mendelevium Md 0 0 0.00 1955 102 6.58102 * 259.000 Nobelium No 827 0 0.00 1958 102 6.65103 * 262.000 Lawrencium Lr 1,627 0 0.00 1961 102 4.90104 * 261.000 Rutherfordium Rf 0 0 0.00 1964 4 0.00105 * 262.000 Dubnium Db 0 0 0.00 1967 5 0.00106 * 266.000 Seaborgium Sg 0 0 0.00 1974 6 0.00107 * 264.000 Bohrium Bh 0 0 0.00 1981 7 0.00108 * 277.000 Hassium Hs 0 0 0.00 1984 8 0.00109 * 268.000 Meitnerium Mt 0 0 0.00 1982 9 0.00No. AtomicWeight Name Sym. M.P.(°C) B.P. (°C) Density(g/cm3) Earthcrust (%) Discovery(Year) Group* Electronconfiguration Ionizationenergy (eV)↑ Top of tableNotes:• Density of elements with boiling points below 0°C is given in g/l. In a sorted list these elements are shown before other elements that have boiling points >0°C. • Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article).• Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.• The elements marked with an asterisk (in the 2nd column) have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Abbreviations and Definitions:No. - Atomic NumberM.P. - melting pointB.P. - boiling pointAtomic number: The number of protons in an atom. Each element is uniquely defined by its atomic number.Atomic mass: The mass of an atom is primarily determined by the number of protons and neutrons in its nucleus. Atomic mass is measured in Atomic Mass Units (amu) which are scaled relative to carbon, 12C, that is taken as a standard element with an atomic mass of 12. This isotope of carbon has 6 protons and 6 neutrons. Thus, each proton and neutron has a mass of about 1 amu.Isotope: Atoms of the same element with the same atomic number, but different number of neutrons. Isotope of an element is defined by the sum of the number of protons and neutrons in its nucleus. Elements have more than one isotope with varying numbers of neutrons. For example, there are two common isotopes of carbon, 12C and 13C which have 6 and 7 neutrons respectively. The abundances of different isotopes of elements vary in nature depending on the source of materials. For relative abundances of isotopes in nature see reference on Atomic Weights and Isotopic Compositions.Atomic weight: Atomic weight values represent weighted average of the masses of all naturally occurring isotopes of an element. The values shown here are based on the IUPAC Commission determinations (Pure Appl. Chem. 73:667-683, 2001). The elements marked with an asterisk have no stable nuclides. For these elements the weight value shown represents the mass number of the longest-lived isotope of the element.Electron configuration: The distribution of electrons according to the energy sublevels (subshells) in uncharged atoms. The noble gas shown in square brackets (e.g. [He]), marks that all the subshells associated with that element are fully occupied by electrons.Energy levels and sublevelsPrincipal energy level(Quantum number: n) Sublevels available(Quantum number: l)123456 1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f 5g6s 6p 6d 6f 6g 6hIonization energy (IE): The energy required to remove the outermost electron from an atom or a positive ion in its ground level. The table lists only the first IE in eV units. To convert to kJ/mol multiply by 96.4869. Reference: NIST Reference Table on Ground states and ionization energies for the neutral atoms. IE decreases going down a column of the periodic table, and increases from left to right in a row. Thus, alkali metals have the lowest IE in a period and Rare gases have the highest.Other resources related to the Periodic Table

2017-12-04 20:13:50 UTC

gary come home

JohnWilkesBooth — 2017-12-05 15:13:56 UTC

Гэри, теперь я знаю, что был неправ
Я перепутался, и теперь ты ушел
Гэри, извините, я пренебрег вами
О, я никогда не ожидал, что ты убежешь
И оставим меня в покое
Твой мяу прямо сейчас звучит как музыка для меня
Пожалуйста, приходите домой, потому что я скучаю по тебе, Гэри

[Хор]
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой

[Стих 2]
Гэри, разве ты не видишь, что я слепой?
Я сделаю все, чтобы передумать
Больше, чем домашнее животное, ты мой лучший друг
Слишком здорово забыть, вернись, потому что мы семья
И простите меня за то, что вы хотите бродить
И теперь мое сердце бьется как самый грустный метроном
Где-то я надеюсь, что вы читаете мое последнее трехсловное стихотворение

[Хор]
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, приходите домой
Гэри, ты не вернешься домой?
Geri, teper' ya znayu, chto byl neprav
YA pereputalsya, i teper' ty ushel
Geri, izvinite, ya prenebreg vami
O, ya nikogda ne ozhidal, chto ty ubezhesh'
I ostavim menya v pokoye
Tvoy myau pryamo seychas zvuchit kak muzyka dlya menya
Pozhaluysta, prikhodite domoy, potomu chto ya skuchayu po tebe, Geri

[Khor]
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy

[Stikh 2]
Geri, razve ty ne vidish', chto ya slepoy?
YA sdelayu vse, chtoby peredumat'
Bol'she, chem domashneye zhivotnoye, ty moy luchshiy drug
Slishkom zdorovo zabyt', vernis', potomu chto my sem'ya
I prostite menya za to, chto vy khotite brodit'
I teper' moye serdtse b'yetsya kak samyy grustnyy metronom
Gde-to ya nadeyus', chto vy chitayete moye posledneye trekhslovnoye stikhotvoreniye

[Khor]
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, prikhodite domoy
Geri, ty ne vernesh'sya domoy?

JohnWilkesBooth — 2017-12-05 17:11:31 UTC

JohnWilkesBooth — 2017-12-05 17:12:54 UTC

rare footage of german u boat monents before being hit by torpeedo

JohnWilkesBooth — 2017-12-05 17:37:46 UTC

spongebob is a sponge named bob

2017-12-05 17:48:22 UTC

DU DUDBDJUDDSUSUUSUSUUUUUUUUUuuu

JohnWilkesBooth — 2017-12-05 17:49:42 UTC

when you try to think rationally but you think to hard and get a rash

Hello. Yes I live Here. No, No I did not kill my Neighbor's dog. Did I kill my Neighbor? Yes. Why are you asking? What do you mean I'm under arrest? OH FUCK, FUCK, FUCK, FUCK, FUCK. STOP SHOOTING! AHHHH MY LEG! FUCK ITS BLEEDING EVERYWHERE! AHHH YOU’RE HURTING ME. I'M NOT RESISTING, NO I’M NOT, WHAT DO YOU MEAN WHAT AM I DOING I'M HAVING A FUCKING SEIZURE. WHAT, NO I’M NOT LYING, WAIT DON'T SHOOT ME AGAI-

2017-12-05 17:51:01 UTC

JohnWilkesBooth — 2017-12-05 17:51:38 UTC

JohnWilkesBooth — 2017-12-05 17:51:54 UTC

JohnWilkesBooth — 2017-12-05 17:53:47 UTC

JohnWilkesBooth — 2017-12-05 17:54:28 UTC

Robert's got a quick hand
He'll look around the room, he won't tell you his plan
He's got a rolled cigarette, hanging out his mouth he's a cowboy kid
Yeah found a six shooter gun
In his dad's closet hidden oh in a box of fun things, I don't even know what
But he's coming for you, yeah he's coming for you

All the other kids with the pumped up kicks
You'd better run, better run, out run my gun
All the other kids with the pumped up kicks
You'd better run, better run, faster than my bullet
All the other kids with the pumped up kicks
You'd better run, better run, out run my gun
All the other kids with the pumped up kicks
You'd better run, better run, faster than my bullet

Daddy works a long day
He be coming home late, he's coming home late
And he's bringing me a surprise
'Cause dinner's in the kitchen and it's packed in ice
I've waited for a long time
Yeah the slight of my hand is now a quick pull trigger
I reason with my cigarette
And say your hair's on fire, you must have lost your wits, yeah

All the other kids with the pumped up kicks
You'd better run, better run, out run my gun
All the other kids with the pumped up kicks
You'd better run, better run, faster than my bullet

JohnWilkesBooth — 2017-12-05 17:56:33 UTC

JohnWilkesBooth — 2017-12-05 17:57:19 UTC

JohnWilkesBooth — 2017-12-05 17:59:03 UTC

Hello mr jeffersonNo I did not poop in your front yardNo i did not eat your grassI never said you were blindNo i am not calling you a liarI did NOT steal your potatoes NO YOU'RE A POTATONO YOU’RE RAISING YOUR VOICEYOU CAN'T TALK ABOUT MY MOM LIKE THATMom!MOM!MR JEFFERSON CALLED YOU A POTATOMom what are you doingMOM sTOPGet me out of tHe cAR MOMslOW DOWNTRUCK-

2017-12-05 21:20:32 UTC

yourmomisgay23 — 2017-12-06 13:17:23 UTC

yourmomisgay23 — 2017-12-06 13:40:16 UTC

HOMIE GO BUY EGGS FOR BART

2017-12-06 17:57:33 UTC

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yourmomisgay23 — 2017-12-08 13:46:28 UTC

yourmomisgay23 — 2017-12-08 13:52:56 UTC

NORMIES GET OUT!

yourmomisgay23 — 2018-01-29 13:00:49 UTC

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yourmomisgay23 — 2018-01-29 13:03:38 UTC