1.  NaCl Sodium chloride  LiF Lithium fluoride  CaBr Calcium bromide  AlPO 4 Aluminum phosphate  KI Potassium iodide  BaO Barium oxide  CsS Cesium sulfide  Na 2 O Sodium oxide

3.  An ionic compound is an overall neutral substance that is made from a positive and negative ions. Electrons are gained and lost.  The positive ions are typically metals (Na + ) and the negative ions are typically nonmetals (F - ). Sometimes the ion can be a polyatomic ion.  Ex : Cyanide CN - or Phosphate PO 4 3-

4.  The name of the positive ion stays the same.  Sodium stays sodium, lithium stays lithium, etc.  The transition metals are special because they will need a roman numeral to represent the ion’s oxidation state (charge)  Cu 2+ is Copper (II) and Cu 3+ is Copper (III).

5.  Negative ions will have a name change if they are only a nonmetal. The ending changes to -ide. Certain nonmetals have unique roots if they do not end in –ine. carb- nitr- phosph- ox- sulf- selen-  Polyatomic ions that are negative will not have a name change.

6.  Follow the ion list on the table to determine the charges of most elemental ions.

7.  When the compound does not have any added subscripts, the charges were equal but opposite.  CaO AlPO 4 NaNO 3 LiF None of these compounds have added subscripts. The ions have equal but opposite charges.

8.  When the compound has added subscripts, it is to balance the positive and negative ionic charges. The charges come from the opposite ion’s charge. Reduce the numbers. Just criss cross the numbers only. Place polyatomic ions inside parenthesis.