1. Notes #3: Polyatomic Naming (Ionic Bonds)
WCHS Chemistry
***Get out your Periodic Table***

2. Polyatomic Naming Binary
BINARY vs. POLYATOMIC
KCN = Potassium Cyanide
CaSO4 = Calcium Sulfate
NaHCO3 = Sodium Bicarbonate
NH4OH = Ammonium Hydroxide
CaF2 = Calcium Fluoride
Na3N = Sodium Nitride
BaCl2 = Barium Chloride
Polyatomic Naming
Polyatomic Ions = Many atoms that interact as a single unit
Ex: NO3-1, ClO-1
Binary
2 ions
Cation (metal) 1st
Anion (non-metal) 2nd = “ide” ending

3. NAMING POLYATOMIC IONS
Cation goes first! Be careful of NH4+1
Anion goes second. PAY ATTENTION TO DETAILS!
Nitrate = Nitrite = Nitride =
CaCO3 __________________________ K2SO4 ___________________________
MgBr2 __________________________ Na2CO3 ___________________________
NH4OH _________________________________
NO NO N-3
Calcium carbonate
Potassium sulfate
Magnesium bromide
Sodium carbonate
Ammonium hydroxide

4. WRITING POLYATOMIC FORMULAS
Label the charges of the ions!
The total charge MUST equal ZERO!
RULE: If you need 2 or more of polyatomic:
Use ( ) around ONLY the (poly ion)
Ex: Ca(ClO) Al2(SO4)3
Sodium bicarbonate _________potassium chloride ________
Sodium sulfate ____________ calcium hydroxide _________
Ammonium carbonate ____________
KCl
NaHCO3
Na2SO4
Ca(OH)2
(NH4)2CO3