Which of the following is the correct chemical formula for copper(II) bromide?

• A. Cu2Br
• B. CuBr
• C. CuBr2
• D. Cu2Br2

Answer: (C)

Verified step by step guidance

1. Identify the oxidation state of copper in copper(II) bromide. The Roman numeral II indicates that copper has a +2 charge, so Cu is Cu^{2+}.
2. Determine the charge of the bromide ion. Bromide (Br) is a halide ion with a charge of -1, so Br is Br^{-}.
3. To write the correct formula, balance the total positive and negative charges so the compound is electrically neutral.
4. Since copper has a +2 charge and bromide has a -1 charge, you need two bromide ions to balance one copper ion: Cu^{2+} and 2 Br^{-}.
5. Write the formula by placing the number of ions as subscripts: CuBr_{2}.