1. Naming Compounds

2. Ionic Compounds The net (final) charge of the compound will be ZERO! This means that there must be equal amounts of positive and negative charges – not necessarily always equal charges on the ions.

3. Naming ions Metal ions have their original name Metals with multiple oxidation numbers (possible charges) will need to include the specific oxidation number –Iron (II) or Tin (IV) Non-metals keep the same base name, but change the ending to “ide” –Chlorine becomes chloride –Sulfur becomes sulfide

4. Practice Naming KCl potassium chloride Mg 3 N 2 magnesium nitride CuI Copper (I) iodide (copper has +1 charge) FeO Iron (II) oxide (iron has +2 charge)

5. Writing Chemical Formulas Total Charge must equal zero If there is only one of the atom, not subscript number is given - NaCl Formulas are typically written in reduced form (H 2 O not H 12 O 6 ) Shortcut – sometimes you can simple take the ion charges and put them as the subscripts of the other elements –Fe +3 + O -2 -> Fe 2 O 3

6. Practice Writing Formulas magnesium chloride Mg +2 + Cl -1 -> MgCl 2 sodium phosphide Na +1 + P -3 -> Na 3 P barium nitride Ba +2 + N -3 -> Ba 3 N 2 copper (II) iodide Cu +2 + I -1 -> CuI 2

7. Polyatomic Ion Names AmmoniumNH 4 +1 SulfateSO 4 -2 CarbonateCO 3 -2 NitrateNO 3 -1 ChlorateClO 3 -1 CyanideCN -1 BicarbonateHCO 3 -1 HydroxideOH -1 PeroxideO 2 -2 PhosphatePO 4 -3

8. Naming with Polyatomic Ions Metals are named as usual Polyatomic ions use their specific names –NO 3 – nitrate –NO 2 – nitrite –OH – hydroxide –SO 4 – sulfate Name simply combines ion names –MgSO 4 is magnesium sulfate If more than one polyatomic ion is needed, it is put in parenthesis and given a subscript –Mg(OH) is magnesium hydroxide (two hydroxides needed)

9. Practice Writing Names with Polyatomic Ions KClO 3 potassium chlorate Mg(NO 3 ) 2 magnesium nitrate Na 2 SO 3 sodium sulfite Fe 2 (CO 3 ) 3 Iron (III) carbonate (iron has +3 charge)

10. Practice Writing Formulas magnesium phosphate Mg +2 + PO 4 -3 -> Mg 3 (PO 4 ) 2 sodium peroxide Na +1 + O 2 -2 -> Na 2 O 2 ammonium nitride NH 4 +1 + N -3 -> (NH 4 ) 3 N copper (II) hydroxide Cu +2 + OH -1 -> Cu(OH) 2