1. Opener  You know that ions can have positive and negative charges. How do you think ionic compounds form.  For example: how many Bromide ions would bond with a Calcium ion? What would you call this substance??

2. Ionic Formulas  When cations and anions bond together, they form salts.  The overall charge of an ionic compound is zero. For example: Na + + Cl - → NaCl

3. Ca 2+ + 2Cl - → CaCl 2 * The coefficient (the number before the atomic or molecular formula) tells you how many atoms or molecules you have. The subscript (the number below the line) tells you how many of the preceding atom you have.

4. More examples: What should the coefficients be in these equations? Na + + O 2- → Na 2 O Al 3+ + O 2- → Al 2 O 3

5. More examples: What should the coefficients be in these equations? 2Na + + O 2- → Na 2 O Al 3+ + O 2- → Al 2 O 3

6. More examples: What should the coefficients be in these equations? 2Na + + O 2- → Na 2 O 2Al 3+ + 3O 2- → Al 2 O 3

7. Now practice: Ca 2+ + O 2- → Na + + N 3- → Ca 2+ + N 3- →

8. Now practice: Ca 2+ + O 2- → CaO 3Na + + N 3- → Na 3 N 3Ca 2+ + 2N 3- → Ca 3 N 2

9. Now practice: K + + S 3-  Be 2+ + F -  Al 3+ + I -  Ga 3+ + O 2- 

10. Monoatomic ions (ions made up of only one atom) are named by changing the end of the element name to -ide for example: bromine (Br) becomes bromide (Br - ) tellurium (Te) becomes telluride (Te -2 ) sulfur (S) becomes sulfide (S -2 )

11.  When naming an ionic compound, you first give the name of the cation element, then the anion with the -ide ending.  For example; NaCl is sodium chloride Lets name the compounds from the last practice slide….

12. Now practice: Ca 2+ + O 2- → CaO 3Na + + N 3- → Na 3 N 3Ca 2+ + 2N 3- → Ca 3 N 2

13. Now practice: Ca 2+ + O 2- → CaO Calcium Oxide Na + + N 3- → Na 3 N Sodium Nitride Ca 2+ + N 3- → Ca 3 N 2 Calcium Nirtide

14. Polyatomic Ions  Polyatomic ions are ions made up of more than one atom  There are 15 polyatomic ions (ions made up of more than one atom) that you are responsible for memorizing before the test. (If you see the formula, you need to be able to tell me the name.) They can be found on page 178 of the text.

15.  Here are some of them….  OH- hydroxide  SO 4 2- sulfate  SO 3 2- sulfite  O 2 2- peroxide  NO 2 - nitrite  NO 3 - nitrate  MnO 4 - permanganate Flashcards!

16. The same rules apply when dealing with polyatomic ions. (remember, the charge associated with the polyatomic ion applies to the entire ion) K + + CN - → KCN 2Na + + O 2 2- → Na 2 O 2 Mg 2+ + 2NO 2 - → Mg(NO 2 ) 2 (by putting parenthesis around the Nitrite portion of the compound, the following subscript tells us that there are 2 nitrite ions for every one Magnesium ion in this compound)

17. More Practice: Li + + MnO 4 - → Ca 2+ + NO 2 - → Na + + SO 3 2- →

18. More Practice: Li + + MnO 4 - → LiMnO 4 Ca 2+ + 2NO 2 - → 2Na + + SO 3 2- →

19. More Practice: Li + + MnO 4 - → LiMnO 4 Lithium Permanganate Ca 2+ + 2NO 2 - → 2Na + + SO 3 2- →

20. More Practice: Li + + MnO 4 - → LiMnO 4 Lithium Permanganate Ca 2+ + 2NO 2 - → Ca(NO 2 ) 2 2Na + + SO 3 2- →

21. More Practice: Li + + MnO 4 - → LiMnO 4 Lithium Permanganate Ca 2+ + 2NO 2 - → Ca(NO 2 ) 2 Calcium Nitrite 2Na + + SO 3 2- →

22. More Practice: Li + + MnO 4 - → LiMnO 4 Lithium Permanganate Ca 2+ + 2NO 2 - → Ca(NO 2 ) 2 Calcium Nitrite 2Na + + SO 3 2- → Na 2 SO 3

23. More Practice: Li + + MnO 4 - → LiMnO 4 Lithium Permanganate Ca 2+ + 2NO 2 - → Ca(NO 2 ) 2 Calcium Nitrite 2Na + + SO 3 2- → Na 2 SO 3 Sodium Sulfite

24.  Closer……answer the opener question now that you’ve had the notes!! How many Bromide ions would bond with a Calcium ion? What would you call this substance??