C2

Formation of ions

-charged particles.

-made when electrons are transferred.

-ions are formed when atoms gain or lose electrons for a full outer shell.

-metal atoms lose electrons from their outer shell to form positive ions.

-Non metal atoms gain electrons into their outer shell to form negative ions.

-if two electrons are lost, the particle now has two more protons than electrons. 

so charge is +2.

Group 1 = 1+ Group 2 = 2+ Group 6 = 2- Group 7 = 1-.

Lose lose gain gain!

Ionic bonding

-oppositely charged ions are strongly attached to one another by electrostatic force.

-called ionic bonding. (holds ions together to make an ionic compound)

Dot and cross diagrams show how ion compounds are formed.

Sodium ions have the formula…