1. Groups of the Periodic Table

2. Alkali Metals  Group 1a  one valence electron  Very reactive!  React with moisture in air—stored under oil or kerosene  Form H 2 in water--fire  Form a basic solution in water  Soft metal  Can cut with knife  Tarnish rapidly

3. Alkaline Earth Metals  Group 2A  2 valence electrons  Reactive, but not as reactive as Alkali Metals  Found in minerals  Essential for bones, nerve impulses

4. Transition Metals  B Group  d-block  Harder metals  Form positive ions with a varying charge  Can’t tell number of valence electrons  Colorful solutions  Gemstones-chromium: red; titanium and cobalt: blue  Found free (uncombined) in nature  Gold and silver  Coinage metals

5. Halogens  Group 7A  7 valence electrons  Very reactive nonmetals  Form negative ions  Group has gases, a liquid and a solid  Ions important to human body

6. Noble Gases  Group 8A  Contain a full outer shell  8 valence electrons  Except He has only 2—still full!  Very unreactive  Also called Inert Gases  Can be used in areas to prevent combustion