Chemical Nomenclature

3 Systems of Naming Compounds

Traditional System

• Name the metal first; use Latin names of metals.

• In binary compounds the nonmetal takes the suffix

–ide

.

• Some transition metals (electrons in d orbitals) can form more than one ion • The ion with the lower charge takes the suffix –ous • The ion with the higher charge takes the suffix –ic.

Traditional system II

• Element • Copper • Iron • Nickel • Manganese • Mercury Lower chg Cuprous +1 Ferrous +2 Nickelous Manganous Mercurous Higher Chg.

Cupric +2 Ferric +3 Nickelic Manganic Mercuric

Traditional system III

• How can you tell which ion is present?

• Determine the charge on the nonmetal species, and the charge on the metal which balances the negative charge on the nonmetal will reveal which ion is present.

• FeSO 4 Ferrous or Ferric?

– Fe +2 + SO 4 -2 – Ferrous sulfate – What will be the formula of Ferric sulfate?

– Fe 2 +3 (SO 4 ) 3 -2 The – charge on sulfate does not change, only the charge on the + ion has changed. The formula for the compound is changed accordingly.

Traditional system IV

• Cu 2 CO 3 • Cuprous or cupric carbonate?

• Cuprous, Charge of +1 on the copper ion means 2 ions must neutralize –2 charge on carbonate • Formula for cupric carbonate?

• CuCO 3

Stock system

• Instead of Latin names and suffixes to indicate which ion is present, Roman numerals and modern names are used.

• Cu 2 CO 3 • Copper (I) carbonate • CuCO 3 • Copper (II) carbonate • Use the same system for any transition metal which forms more than one ion.

Prefix system

Use the following prefixes to denote how many ions or atoms are present • 1 • 2 mono di • 3 • 4 tri tetra • 5 penta • 6 hexa • 7 • 8 hepta octa • 9 non • 10 deca • 12 dodeca-

Prefix system

• Monocopper monocarbonate • CuCO 3 • Most often the mono- prefix is understood in the same way as a subscript of 1 is understood • Dicopper carbonate • Cu 2 CO 3 • Dialuminum trioxide • Al 2 O 3 • All you have to do is count.

Formula

Comparison of Nomenclature systems

Traditional system Stock system Prefix system Fe 2 (SO 4 ) 3 Ferric sulfate Iron (III) sulfate Diiron trisulfate Cu 3 (PO 4 ) 2 Cupric phosphate Copper (II) phosphate Tricopper diphosphate

Assignment

• Answer questions 13-20 p. 170 • What movie for Friday??