Halogens Group 17 Seven valence electrons -1 charge Very reactive Gained 1 electron Very reactive

Noble Gases Group 18 Octet of valence electrons. (Full valence shell) Inert – do not react

Metalloids Other Non-Metals Other Metals B, Si, Ge, As, Sb, Te, Po H, C, N, O, P, S, Se Other Metals Al, Ga, In, Sn, Tl, Pb, Bi

Lanthanide and Actinide Series The Lan. Series is Period 6 The Act. Series is Period 7 Also known as Rare Earth Elements

When the # of protons change… What do you create? A new element! Gaining or losing protons will result in a new element. Example, Sodium (Na) has an atomic number of 11, so the number of proton is 11. When sodium gains 1 proton, it now has 12 protons. And it becomes magnesium (Mg), because atomic number of Mg is 12 so the number of proton is also 12. Calcium (Ca) has an atomic number of 20, so the number of proton is 20. When calcium loses 1 proton, it now has 19 protons. And it becomes potassium (K) because the atomic number of K is 19 so the number of proton is also 19.

When the # of electrons change… What do you create? An ion Ion: atoms that have lost or gained one or more electrons. Cation Anion positively charged ion negatively charged ion Lost electron Gained electron # proton > # electron # proton < # electron Ex: Na+, Ca+2 Ex: O-2, Cl- Another name for the charge on an ion is oxidation number.