1. Valence Electrons and Ions

2. Periodic Table of the Elements

3. Ion Charge Reactive elements can become stable (full valence shell) by gaining or losing electrons. An atom that gains electrons becomes a negatively charged ion called an anion. Non-metals gain electrons. An atom that loses electrons becomes a positively charged ion called a cation. Metals lose electrons.

4. Magnesium ( 24 12 Mg) Mgatom Mg 2+ ion charge = +12-12 (0)charge = +12-10 Magnesium atom loses 2 valence electrons Mg 2+ has a full valence shell and is stable

5. Nitrogen ( 14 7 N) N atom N -3 ion charge = +7 – 7 (0) charge = +7 - 10 Nitrogen atom gains 3 valence electrons The nitride ion has a full valence shell, so it is stable -3

6. What will the charge be? +1 +2 +3 -3 -2

7. CLASSWORK Complete the back of the handout “Formation of Ions”