group 1, hydrogen is not a member. good conductors of heat and electricity, very reactive, only 1 valence electron, most reactive metals, never found in nature uncombined
group 3-12, largest group on periodic table, good conductors of heat and electricity, compounds with these elements are usually brightly colored, most have 1 or 2 valence electrons
group 13, 3 valence electrons, composed of a metalloid and metal, aluminum is important because it is light, strong, and does not corrode
group 14, 4 valence electrons, composed of 1 nonmetal, 2 metals, 2 metalloids, carbon forms 5 million compounds and is called 'basis of life'.
group 15, 5 valence electrons, tend to share electrons, nitrogen is the most abundant element in the earth's atmosphere
group 16, 6 valence electrons, tend to share electrons, oxygen is the most abundant element in the earth's crust
group 17, 7 valence electrons, most reactive nonmetals, never found uncombined in nature, halogens combined with metals form salts
group 18, normally unreactive, also called inert gases, 8 valence electrons filled outer shell