1. 3 Sets of Rules of Naming Rules
Class or Type I - Ionic Bond between metal predictable + charge and a negative nonmetal or polyatomic ion ; name cations, anion ends in “ide”
Examples: NaCl – sodium chloride ; MgCl2, magnesium chloride
Class or Type II- Ionic Bond with variable oxidation state transition metal; Roman numerals used to specify charge of transition metal
Example: CuCl2 – copper(II) chloride
Class or Type III – Covalent bonds between Two nonmetals; uses prefixes
Example: CO2 – carbon dioxide; N2O4 – dinitrogen tetroxide

2. Location of First Element in Formula determines class rules+1
Class or Type I +2 +3
Class or Type II
Class or Type III +1 +2

3. Location of First Element in Formula determines class rules+1
Class or Type I +2 +3
Class or Type II
Class or Type III +1 +2

4. Compare the charges of groups 1A,2A and 3A to 6B, 7B and 8B
Compare the charges of groups 1A,2A and 3A to 6B, 7B and 8B. What is different?

6. Difference between Class I and II Compounds: Class I only 1 possible formula; Class II two or more possible formulas
Sodium chloride
Copper(II) Chloride is blue
Only 1 compound possible
NaCl
Copper(I) chloride is green
CuCl
CuCl2

7. Charges of Class I vs Class II Cations
CLASS I CATIONS
CLASS II CATIONS
Group 1
Group 2
Li +1
Na +1
Mg +2
K +1
Ca+2
Rb +1
Sr +2
Cs +1
Ba+2
Ag +1
Cd +2
Zn +2
Ga +3
In +3
Al +3

8. Rules for Naming Class II Compounds
Metal cation first, negative ion second
+ Charge of metal in written in Roman Numerals in ( )
For neutral compound: sum of + = sum of –
Final answer must be simplest ratio

9. Example Problems: Name CuCl and CuCl2
Example #1: CuCl:
Cu = transition metal charge = ?
Cl group 7 charge = -1; 1 Cl present in formula
? (-1) = 0 ;
Copper(I) Chloride
? = +1

10. Example #2: Name CuCl2 CuCl2: Cu = transition metal charge = ?
Cl group 7 charge = -1; 2 Cl present in formula
? (-1) = 0 ;
Copper(II) Chloride
? = +2

11. Practice: Name the following compounds
FeCl3
? + 3(-1) = 0; ? = +3
iron(III) chloride
CuSO4
Recall [SO4] -2 ; ? + 1(-2) = 0; ? = +2
Copper(II) sulfate

12. Practice: Name the following compounds
Co3(PO4)2
Recall PO4-3 : - charge = 2(-3) = -6
? + 2(-3) = 0; ? = +6; however . . .
There are 3 cobalt ions, charge on each cobalt is +6/3 =+ 2
cobalt(II) phosphate

13. Class II compounds: Writing Formulas
Charge on transition metal will be given in ( )
Use periodic table or polyatomic ion list to determine negative charge.
Sum of charges must be zero.
If + charge ≠ - charge, use “Criss-Cross” technique
Final subscripts must be simplest ratio.

14. Class II Writing Formulas: Examples
What is the formula of
What is the formula of
Iron(II) = Fe+2
O group 6 = O-2
Iron(III) = Fe+3
O group 6 = O-2
Fe+3O-2 →
Fe2O3
Fe+2O-2 → FeO

15. Practice – what is the formula of tin(IV) oxide?
Tin(IV) = Sn+4
Oxide = O-2 (group 6)
Sn+4 O-2
Sn2O4 - not in simplest terms
Final Ans: SnO2

16. Practice write formulas for each of the of following:
nickel(II) phosphate
Ans: Ni+2 PO4-3
Ni3(PO4)2
Manganese(II) nitrate
Ans: Mn+2 NO3-1
Mn(NO3)2