Families of Elements Section 3.3

Major Classifications Metals Shiny solids Easy to stretch and shape Good conductors of heat and electricity Usually form CATIONS Semiconductors Intermediate conductors of heat and electricity Nonmetals Solids, liquids, or gases Solids are usually dull and brittle Poor conductors of heat and electricity Usually form ANIONS

Alkali Metals

Alkali Metals Group 1 (first vertical column) All are relatively soft metals All are highly reactive (explode in water) All have one valence electron (one electron in their outer shell) All form cations with a +1 charge when they lose that valence electron

Alkaline Earth Metals

Alkaline Earth Metals Group 2 (second vertical column) All are reactive, but less-reactive than Alkali metals All have two valence electrons (two electrons in their outer shell) All form cations with a +2 charge when they lose those valence electrons

Transition Metals

Transition Metals Groups 3 to 12 Much less reactive than Alkali Metals or Alkaline Earth Metals Some have different numbers of valence electrons All form cations Many different cations are possible for any one element (Au+, Au3+)

Halogens

Halogens Group 17 Highly reactive, especially with alkali metals Range from gas to liquid to solid as you move down the column All form diatomic molecules (like Cl2) All form anions with a charge of -1.

Noble Gases

Noble Gases Group 18 All are inert, or unreactive All are gases All have full valence electron shells Most do not form cations or anions, but remain as atoms.