https://padlet.com/304807/m8lry1t4v0rk en-us 2017-12-06 17:24:10 UTC 2017-12-06 17:33:08 UTC hello@padlet.com 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213814291 any of the gaseous elements helium, neon, argon, krypton, xenon, and radon, occupying Group 0 (18) of the periodic table. They were long believed to be totally unreactive but compounds of xenon, krypton, and radon are now known.]]> 2017-12-06 17:25:32 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213814291 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213814658 any of the set of metallic elements occupying a central block (Groups VIIB–VIII, IB, and IIB, or 4–12) in the periodic table, e.g., iron, manganese, chromium, and copper. Chemically they show variable valence and a strong tendency to form coordination compounds, and many of their compounds are colored.]]> 2017-12-06 17:26:11 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213814658 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213815204 The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium.]]> 2017-12-06 17:27:15 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213815204 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213815573 The lanthanide or lanthanoid series of chemical elements comprises the fifteen metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium.]]> 2017-12-06 17:27:52 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213815573 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213815975 any of the elements beryllium, magnesium, calcium, strontium, barium, and radium, occupying Group IIA (2) of the periodic table. They are reactive, electropositive, divalent metals, and form basic oxides that react with water to form comparatively insoluble hydroxides.]]> 2017-12-06 17:28:36 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213815975 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213817143 The alkali metals are a group in the periodic table consisting of the chemical elements lithium, sodium, potassium, rubidium, caesium, and francium]]> 2017-12-06 17:30:38 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213817143 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213817502 put together or place in a group or groups.]]> 2017-12-06 17:31:22 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213817502 304807 https://padlet.com/304807/m8lry1t4v0rk/wish/213818114  A period is the name given to a horizontal row of the periodic table. ... Period 1 contains only two elements: hydrogen and helium.]]> 2017-12-06 17:32:25 UTC https://padlet.com/304807/m8lry1t4v0rk/wish/213818114