What is the correct name for the ionic compound with the formula MnI_2?

• A. Magnesium iodide
• B. Manganese(III) iodide
• C. Manganese(II) iodide
• D. Manganese diiodide

Answer: (C)

Verified step by step guidance

1. Identify the cation and anion in the formula MnI_2. Here, Mn is the metal cation (manganese) and I is the anion (iodide).
2. Determine the charge of the iodide ion. Iodide (I^-) is a halide ion with a charge of -1.
3. Since there are two iodide ions, the total negative charge is 2 × (-1) = -2. To balance this, the manganese cation must have a charge of +2.
4. Use the Roman numeral system to indicate the charge of the manganese cation in the compound name. Because manganese has a +2 charge here, it is named Manganese(II).
5. Combine the cation and anion names to form the full name: Manganese(II) iodide. This correctly reflects the formula MnI_2.