The Periodic Table

Vertical rows on the periodic table are called?

Groups

Horizonal rows on the periodic table are called?

Periods

Alkali Metals

• 1 electron on their outer shell

• Reactive

• Lithium

Alkaline Earth Metals

• 2 electrons on their outer shell

• Reactive, but less than alkali metals

• Calcium

Halogens

• 7 electrons on their outer shell

• Reactive

• Chlorine

Nobel Gases

• 8 electrons on their outer shell - full shell

• Not reactive, stable

• Neon

Valency of an atom

The number of electrons an atom must gain or lose to have a full outer shell