Multivalent Ionic Compounds
Multivalent Compounds There are some elements on the periodic table that can form different Cations because of their valence electrons. For example: Copper It forms both Cu+ and Cu2+ You will also notice it has two names depending on the charge: Copper (I) Cu+ Copper (II) Cu2+
Writing Formulas I 1 II 2 III 3 IV 4 V 5 VI 6 VII 7 We will be using the Stock system, the English name of element and the cation charge in Roman numerals The Roman numeral tells you how many charges you are dealing with Manganese (II) will have 2 charges! Mn2+ I 1 II 2 III 3 IV 4 V 5 VI 6 VII 7
Let’s Try! Using the same Crossover method you have been taught, write the formula for Copper (II) Chloride. Cu²+ and Cl- Crossover Method =
Practice! Chromium (III) Phosphide Ruthenium (IV) Selenide Palladium (II) Bromide Iridium (III) Sulfide Gold (I) Nitride Copper (I) Oxide Copper (II) Oxide CrP RuSe2 PdBr2 Ir2S3 Au3N Cu2O CuO
Naming If the metal is a multivalent ion you will need to figure out the Roman Numeral based on the formula! Example Name CoI2 Answer - Cobalt (II) Iodide
This is How!! – YES YOU HAVE TO MATH Multiply the charge on the anion by the number of anions and then divide by the number of cations to get the roman numeral. Write the names for Fe2S3 SnO2
Fe2S3 S²- 3x2 = 6 6/2 = 3 Roman Numeral is (III) Answer Iron (III) Sulfide
SnO2 O²- 2x2 = 4 4/1 = 4 Roman Numeral is (IV) Answer Tin (IV) Oxide AND THAT IS WHY YOU CAN’T JUST FLIP BACK!
Practice CrF3 TiO2 AuCl3 Fe2O3 FeCl2 PdTe Os2O3 Chromium (III) Fluoride Titanium (IV) Oxide Gold (III) Chloride Iron (III) Oxide Iron (II) Chloride Palladium (II) Telluride Osmium (III) Oxide