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 ElementLower chgHigher Chg. CopperCuprous +1Cupric +2 IronFerrous +2Ferric +3 NickelNickelousNickelic ManganeseManganousManganic MercuryMercurousMercuric

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 1mono- 2di- 3tri- 4tetra- 5penta- 6hexa- 7hepta- 8octa- 9non- 10 deca- 12dodeca-

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.

Comparison of Nomenclature systems FormulaTraditional 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 p. 170 What movie for Friday??