Naming Ionic Compounds With Cation With More Than One Charge

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Chemistry - Naming Ionic Compounds with Cation Ions of More than One Charge
A. Chemical Name to Chemical Formula
1. Write down the symbol(s) and charge of cation (look at Roman numeral for charge), then the anion.
2a. The number of positive ions has to equal the number of negative ions.
2b. Determine the number of each ion to make the charges equal.
3. To get correct chemical formula

Each number of ions will be the subscript of the ion in the final chemical formula.
When writing chemical formula, never shows charges of ions.

Example: Chromium (III) sulfate
Step 1 Cr³⁺ SO₄^2-
Step 2 Need two cations, Cr³⁺, Cr³⁺ and three anions,SO₄^2-, SO₄^2-, SO₄^2-
Step 3 Cr₂(SO₄)₃
More Examples: Iron (III) nitride, Cobalt (IV) sulfite {Answer: Fe₁N₁, Co₁(SO₃)₂}

B. Chemical Formula to Chemical Name
1a.Write down the chemical name for the cation.
1b. To determine the Roman numeral, need to determine the charge on the cation.
1c. Figure out the anion charge, then find total negative charge (also total positive charge) and divide by the number of cations.
2. Write down the chemical name for the anion.

Example: Sn₁(CO₃)₂
Step 1a Tin
Step 1b&c CO₃ has 2- charge, there are 2 so -4 total charge=+4 charge, only one cation, therefore each Sn has 4+ charge
Step 2 Tin (IV) carbonate
More Example: Fe₁(OH)₃ (Answer: Iron (III) hydroxide)