1. IONIC BONDING Metal + Nonmetal

2. Valence Electrons vs. Charge Valence Electrons = Outer Shell Electrons # Valence Electrons = Group (A) # Charge When an atom LOSES electrons  ( + ) charge [metals] When an atom GAINS electrons  ( - ) charge [non-metals] REMEMBER: electrons are NEGATIVELY charged neutral atoms have an equal number of electrons and protons

3. 1A 2A3A 4A 5A6A 7A 8A +1 +2 +3 +/-4+/-4-3 -2 0 Group Number Charge

4. Electron Configuration -METALS Li 1s 2 2s 1 -1e - Be 1s 2 2s 2 -2e - Na 1s 2 2s 2 2p 6 3s 1 -1e - Mg 1s 2 2s 2 2p 6 3s 2 -2e - Al 1s 2 2s 2 2p 6 3s 2 3p 1 -3e - K 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 -1e - Ca 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 -2e -  Li + 1s 2 Be 2+ 1s 2 Na + 1s 2 2s 2 2p 6 Mg 2+ 1s 2 2s 2 2p 6 Al 3+ 1s 2 2s 2 2p 6 K + 1s 2 2s 2 2p 6 3s 2 3p 6 Ca 2+ 1s 2 2s 2 2p 6 3s 2 3p 6

5. Electron Configuration -NON-METALS N 1s 2 2s 2 2p 3 +3 e - O1s 2 2s 2 2p 4 +2 e - F1s 2 2s 2 2p 5 +1 e - P1s 2 2s 2 2p 6 3s 2 3p 3 +3 e - S1s 2 2s 2 2p 6 3s 2 3p 4 +2 e - Cl1s 2 2s 2 2p 6 3s 2 3p 5 +1 e -  N 3- 1s 2 2s 2 2p 6 O 2- 1s 2 2s 2 2p 6 F - 1s 2 2s 2 2p 6 P 3- 1s 2 2s 2 2p 6 3s 2 3p 6 S 2- 1s 2 2s 2 2p 6 3s 2 3p 6 Cl - 1s 2 2s 2 2p 6 3s 2 3p 6

6. WHEN CHARGES ARE EQUAL: Na + F Na 1+ F 1- NaF Mg + O Mg 2+ O 2- MgO WHEN CHARGES ARE UNEQUAL: K + S K 1+ S 2- K 2 S Ca + P Ca 2+ P 3- Ca 3 P 2 Writing Chemical Formulas

7. Sodium and Fluorine Na + F Na 1+ F 1- NaF (1 Na & 1 F) Na  F        + F        - 

8. Magnesium and Oxygen Mg + O Mg 2+ O 2- MgO (1 Mg & 1 O) Mg  O      2+ O        2-2-  

9. Potassium and Sulfur K + S K 1+ S 2- K 2 S (2 K & 1 S) K  S      K + S        2-2-  K  K +

10. Calcium and Phosphorus Ca + P Ca 2+ P 3- Ca 3 P 2 (3 Ca & 2 P) Ca  P      2+ P        3-3-   Ca  P      2+ P        3-3-  Ca    2+