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- Anything that has mass and takes up space or volume
-can consist of an element, compound or mixture
- 3 forms
solid (s)
liquid (l)
gas (g)

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Matter is anything that has mass and takes up space
Mass is a measuremenr that reflects the amount of matter
Matter can change its structure and its composition
Changes in structure and composition lead to changes in the properties of matter

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Ernest Rutherford: gold foil experiment
This experiment had alpha particles (positive charge) shot at gold foil. Most particles went right through which shows that the atom is mostly made of empty space. Some particles reflected showing there is a tiny, dense, center that is positive (nucleus).

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Anion- A negatively charge ion
Atom- The basic unit of a chemical element
Atomic Mass- The mass of an atom of a chemical element expressed in atomic mass units
Atomic Mass Unit (a.m.u.)- A unit of mass used to express atomic and molecular weights
Atomic Number- The number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table
Bohr Model- Depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus
Cation- A positively charged ion
Compound- A thing that is composed of two or more separate elements
Electron- A stable subatomic particle with a charge of negative electricity
Electron Configuration- The electron configuration is the distribution of electrons of an atom or molecule in atomic or molecular orbitals
Element- More than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter
Excited State- In an excited-state atom not all electrons are in the lowest possible energy levels, when goes back to ground state it releases energy as light
Ground State- In a ground-state atom, all electrons are in the lowest possible energy levels
Ion- An atom or molecule that has a non-zero net electrical charge
Isotope- Variants of a particular chemical element which differ in neutron number
Kernel Electron- The remainder of an atom after the valence electrons have been removed
Lewis Dot Diagram- Diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule
Mass Number- The total number of protons and neutrons in a nucleus
Neutron- a subatomic particle of about the same mass as a proton but without an electric charge
Nucleur Charge- The nuclear charge is the total charge of all the protons in the nucleus and the electrons
Nucleon- A proton or neutron
Nucleus- The central and most important part of an atom

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-a method for handling uncertainty in all measurements
- this arises due to the fact that we have different equipment with different degrees of accuracy
- significant figures are associated with measurements and calculations
- chemists do mathmatics when determining sig figs
Ex: atomic masses on periodic table
- conversions (1in.=2.54 cm)

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Qualitative: Describes characteristics
Ex: Size, shape, color, mass, density, etc.

Quantitative: Uses tools for measurement
Ex: Temperature (thermometer), Mass (balance), Volume (graduated cylinder or ruler)

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Properties of Solids:
-definite volume &a shape
-tightly packed particles
-incompressible
-expands a little when heated
-very little movement of particles, vibrational
Properties of Liquids:
-definite volume
-indefinite shape, takes the shape of the container
-loosely packed particles
-initially compressible
-tends to expand when heated
-particles flow
Properties of Gases:
-indefinite shape & volume
-takes the shape of the container
-particles far apart from each other
-compressible
-expands with increasing temperature
-constant random motions

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Scientific method is a systematic approach used in scientific study

Observations lead to questions to be solved
A hypothesis is a when you come up with a tentative solution
“Educated guess”
Perform the experiment
From the results, make a conclusion
A valid conclusion usually agrees with the hypothesis
Repeat the experiment many times to form a theory
A theory tested over a long period of time can become a “law”

What are observations?
We can observe color change, bubbles and fizzing, presence of new material, temperature, odor, and physical characteristics and changes

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Consists of the nucleus, electrons, protons, and neutrons.

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Solid -> liquid FUSION (melting)
solid -> gas SUBLIMATION
liquid -> gas  VAPORIZATION
gas -> liquid CONDENSATION
gas ->solid DECOMPOSITION
liquid -> solid CRYSTALLIZATION

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What is a mole? A mole is a measurement of particles. (Example: the number of atoms of carbon present in 12.000 grams of C-12)

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Crystals that contain attached water molecules are called hydrates, while substances without water are termed anhydrous

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The Gram formula mass of a substance is simply the formula mass expressed in grams instead of atomic mass units. For example the gram formula mass of Ca(OH)
2
Ca= 40x1=40 O=16x2=32. H=1x2=2
Gram formula mass = 74

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JJ Thompson:
-Discovered electron
- made plum pudding model that showed no nucleus and subparyicles scattered everywhere

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The number of protons in an atom is equal to the atomic number of its element

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John Dalton:
-Theory:
1.all matter are composed of inseparable particles called atoms
2. All atoms of one element have the same mass and properties (this is incorrect *isotopes)
3. Compounds are formed by 2 or more atoms
4. Atoms can’t be destroyed, created, or combined (also false because atoms can combined)

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Mole formula: found on Table T in the reference table
# moles= given mass/ gram formula mass
Example: How many grams are in 40.5 mol of sulfuric acid (H2SO4)
1) Write down the information given and the information you need to find. In this case, the questions gives us 40.5, what we need to find is the mass in grams and also the gram formula mass.
2) Find the gram formula mass and plug that number into the equation, along with the mol number included in the question.
3) the equation will look like this 40.5= x/ 98.1g
4) By putting 40.5 over 1, you can cross multiply and get x= 3973.05 which can be reduced to 3970g

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The wave mechanical model is the most recent and most accurate representation of the atom. Energy is viewed in being in waves. This model shows the atom having a dense, positively charged nucleus. Electrons are found within the fuzzy outlines of the waves. The spaces between are known as nodes.

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The percent composition of a substance represents the composition as a percentage of each element compared with the total mass of the compound

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Range of radiation wavelengths which includes the visible light spectrum

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Look at Table T

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- All measurements have some sort of error
- The greater amount of places beyond the decimal point, the more accurate the measurement will be
- All measurements include the actual value plus one guestimated place
- Every measurement must contain a numbered unit
- A less accurate measurement only contains a guestimated value

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Measurements are read from the bottom of the meniscus

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The coefficients represent quantitative information that relates specifically to that reaction. In problems involving chemical reactions, the relative amounts of reactants and products are represented by the coefficients. Coefficients represent both the basic unit and mole ratios in balanced equations

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Isotopes are atoms of the same element that have different numbers of neutrons, and hence have different mass numbers. Isotopes can be identified by using a symbol that indicates both the element and its mass number. EX: C-12 represents a carbon atom with a mass number of 12

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Measures in Celsius or Kelvin
K has no degrees symbol
The change in Celsius equals the change in Kelvin

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Nucleons are subatomicparticles that live inside the nucleus.
Subatomic particles are particles smaller than an atom (e.g., a neutron) or a cluster.

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GROUND: When the electrons occupy the lowest available orbitals, the agom is in ground state. EX: Na-2-8-1 shows the arrangement of electrons for a ground state sodium atom.
EXCITED: When electrons are subjected to stimuli such as heat,light, or electricity, the electron will temporarily move to a higher, more unstable condition called an excited state. EX: Na-2-7-2

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If there is a decimal present think "P" for present. P stands for Pacific coast. If there is no decimal think "A" for absent.

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Neil’s Bohr:
Created Bohr model (planetary model)
Shows electrons traveling around the nucleus in orbits (now called orbitals)

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The empirical formula is the simplest form of that formula
For example :

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A physical change is a change that does not alter the chemical properties of a substance. Ex: Boiling, freezing, mixing

A Chemical change is a reaction in which the composition of a substance is changed. Ex: Rusting, the spoiling of milk, burning paper

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Mass number : add protons and neutrons
Atomic number: same as proton and in electron
Neutrons: subtract atomic mass from number of protons or electrons

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Solid - Matter is held in a rigid form and has definite volume and shape. Strong attractive forces hold particles in fixed locations

Liquid - Less rigid form and the particles have space to move past one another. Do not have a definite shape (takes the shape of the container it is in), but they have a definite volume

Gas - Particles have minimal forces holding them together. Matter in this face do not have a definite shape or volume. Gases spread out indefinitely and fill whatever container they are in. There is a lot of space between gaseous particles.

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Bonding

Any rearrangement of electrons in two atoms that generates a force, causing the atoms to be bound to each other, forming a molecule.

Elements bond to become more stable.

Bonded elements have less energy.

When bonds are formed, energy is released.

As a result of bonding, the different elements in a compound will have full valence shells. (For most that is 8 electrons, or a full octet)

There are different types of bonds:

Ionic Bonding- metals and non metals; metals transfer valence electrons and will have a full inner kernel shell of electrons and non metals accept the electrons to fill their valence shell; metals become cations and non metals become anions; usually an electronegativity difference of 1.7 or greater

Covalent Bonding- A covalent bond is formed when two nuclei share electrons in order to achieve a stable arrangement of electrons.

Metallic Bonding- A metales bond results from the force of attraction of the mobile valence electrons for an atom’s positively charged kernel.

How to write an ionic compound formula using the Periodic Table:

Look for number of valence electrons in each element

Find how many electrons are needed in the non metals

Check oxidation state of both metal and non metal

Write down chemical symbols with metal then non metal

Criss cross oxidation states

Table E on Reference Table

Metals also combine with polyatomic ions

Monoatomic ions=Na+, Cl-, K+, Fe+

Polyatomic ions=made of many

Polyatomic ions will accept electrons from metals

When an element has multiple oxidation states, you need to acknowledge the charge used when naming.

When bonds break, energy is absorbed.(endothermic)

When bonds are formed, energy is released. (Exothermic)

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How to find the mass of a mole
Question: What is the mass of a mole of 02(g)
• In the question is two oxygen atoms. And on Table S, the mass of oxygen is 16g.
• The question is asking for the mass of 2 oxygen atoms, so you must multiply the mass by 2
• The answer is 32.0g

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Group 1 is called the alkali metals

1 valence

Very active metals

Not found unconvinced in nature

As you go down a group the valence electrons are more active and reactive

Silvery white in color

Lose 1 valence electrons when they bond

Group 2 is called the alkaline metals

They’re metals

2 valence electrons

When they bong they lose two valence electrons

Solids at room temp

They are also silvery/ white in color

They’re not as reactive as group one

They are rarely found uncombined

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Amount of space an object takes up
- Techniques :
• liquids -> graduated cylinder
• regular solids -> L•W•H ruler or meterstick
• irregula Solids -> volume displacement

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London Dispersion Forces are present in any molecule, but are far less apparent in asymmetrical molecules where stronger dipole to dipole attractions exist

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Transition metals

Also known as heavy metals

Tend to be very dense

Varying reactivity because they have multiple oxidation states

They have the ability to form more than one ion because of the multiple oxidation states

The have colorful ions and solutions

Halogens

The only group that has elements in all three phases

7 valence

Highly reactive

When they bond they gain an electron

Fluorine is king of electronegativity (4.0)

Noble gases

Very stable because of full valence

Usually do not react in the present of other elements

Relatively inert

Xe can react with F

He is the only group 18 element without a full octet but still has a full valence

They are all monoatomic molecules

Lanthanide and actinide series

Rare earth metals

Above 92 are man made and unstable

Reactivity in metals

Atoms react when they gain lose or share electrons

Metals lose electrons

Across a period metal reactivity decreases

Down a group metal reactivity decrease

Reactivity in nonmetals

Nonmetals gain electrons

Across a period no metal reactivity increase (more protons so they attract more electrons)

Down a group nonmetal reactivity decreases because of shielding

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Metallic character

Best metal is Francium

Across a period metallic character decreases because there are more protons in the same energy level so there a tighter grip on electrons

Down a group metallic character increases because shielding prevents a nucleus from holding electrons so the electrons become more free

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Hydrogen Bonding- A hydrogen. Bond is an intermolecular bond between a hydrogen atom in one molecule and a nitrogen, oxygen, or fluorine atom in another molecule.

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Atoms have different states known as the ground state and the excited state. Ground state is observed when the electron configuration is as seen on the Periodic Table of the Elements. The excited state of an atom is seen when’s the electron configuration is modified #o the outer most electron amount is increased by the shift of an electron from the lower most levels. For example,

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Polar- electronegativity different of .4-1.69; asymmetrical
Non polar- electronegativity different of 0-.39; symmetrical

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Group 17

F2 and Cl2 are gases at rom temperature

Br2 is a liquid at room temperature

I2 is a solid at room temperature

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The amount of mass in a given space; ratio of mass to volume
Formula : D= m/v

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This theory was developed to explain chemical behavior of atoms.

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Periodic trends

Atomic radius:

increase down a group because number of energy levels increases

Across a period it decreases because there’s a stronger pull on electrons

Metallic character

increases down a group because of shielding

Across a period it decreases because increased nuclear charge, ionization energy, and electronegativity

Electronegativity:

Increases as you go across a period because it needs less electrons to form an octet

Decrease down a group because more energy levels

Ionization energy:

Down a group increases because of shielding

Across a period increases because there’s an increased nuclear charge and closer to valence shell

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Kinetic energy - energy of motion ( average kinetic energy = temperature)
Potential energy - stored energy ( phase change)

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- measurement of the % that the measured is "off" from accepted value

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Properties of metals

all metals are solid at room temperature except Hg which is a liquid

Shiny/ have luster

Malleable (can be bent)

Ductile (can be pulled into wire like copper)

Generally have high melting points

Good conductor of heat or electricity

Have metallic bonds

Metals lose electrons to form full valence shells (positive ion)

Properties of nonmetals

can be solid liquid or gas at room temperature depending on melting point

Dull, lack luster

Brittle

Poor conductors of heat an electricity

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Consists of the chemical symbol surrounded by one to eight dots representing valence electrons