Ionic Compounds with Multivalent Metals PDF

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SNC2D – Chemistry: Chemical Reactions

Ionic Compounds with Multivalent Metals Most transition metals and some metals in group 14 (or IVA) are multivalent (they can form ions of different valences, or ionic charge). For example, iron can form Fe2+ and Fe3+ ions, which are named “iron (II)” and “iron (III)”. They can then form different compounds with a particular anion. There are 2 systems of rules for naming compounds with multivalent metals: International (IUPAC) and “Classical” (“ous-ic”). International (IUPAC) System Writing Formulas: 1. Use the regular crisscross method for writing formulas of ionic compounds. The metal is written first, and then the non-metal. 2. For the metal, use the valence (or charge) given in brackets in the name. Examples: copper (II) nitride=Cu(NO3)2

tin (IV) oxide=SnO2

Writing Names: 1. From the formula, “back-cross” the subscripts – this will give you the charges. 2. Write the names of the elements in the same order as the formula (metal first, followed by the non-metal with “ide” suffix) 3. Use Roman numerals in brackets following the metal to indicate the valence (charge). Examples: FeI2= Iron (II) iodide

Cu2O =Copper(I) oxide

Classical System (“ous-ic”) Writing Formulas: 1. Use the regular crisscross method for writing formulas of ionic compounds. The metal is written first, and then the non-metal. Look for the Latin name and charges of the metal in the table of multivalent metals. 2. If the metal has the suffix “ous”, use the lower valence (charge). If it has the suffix “ic”, use the higher valence. Examples: Stannous fluoride=SnF2 ferric sulfide=Fe2S3

Writing Names: 1. From the formula, “back-cross” the subscripts – this will give you the ionic charges. 2. Write the names of the elements in the same order as the formula (metal first, followed by the non-metal with “ide” suffix) 3. For the metal name, use the Latin name, and add the suffix “ous” if the

low valence was used, or the suffic “ic” if the high valence was used. Examples: Cu3N2=Copper(II) Nitride SnS=Tin(II) sulfide SNC2D – Chemistry: Chemical Reactions

Practice I. Write the correct chemical formulas for the following: 1. gold (III) sulfide=Au2S3

8. copper nitride= Cu3N

9. auric sulfide= Au2S3 2. gold (I) oxide=Au2O 10. cupric nitride= Cu3N2 3. bismuth (V) carbide= Bi4C5

4. tin (IV) phosphide=Sn3P4

5. iron (II) bromide=FeBr2

6. lead (IV) oxide=PbO2

Metals with Multiple Ionic Charges (Multivalent Metals) t Bismuth Bi 3 5 bisemutum Chromium Cr 2 3 chromic Copper Cu 1 2 cuprum Gold Au 1 3 aurum Iron Fe 2 3 ferrum Lead Pb 2 4 plumbum Manganese Mn 2 4 magnes Mercury Hg 1 2 hydrargyrum Nickel Ni 2 3 nickel Tin Sn 2 4 stannum

7. stannous sulfide=SnS

Practice II. Write 2 names for the following, using IUPAC and Classical (ous-ic) rules 1. SnF4 = Tin (IV) Fluoride, Stannic Fluoride

2. FeS =Iron (III) Sulfide, Ferrous Sulfide

3. PbO2 = Lead(IV) Oxide, Plumbic Oxide 4. Cu3N= Copper(I) Nitride, Cuprous Nitride 5. AuF3 = Gold(III) Fluoride, Auric Fluoride 6. CuI= Copper(I) Iodide, Cuprous Iodide...