What is the charge of the metal ion in the complex [Fe(NH_3)_2Br_4]^{2-}? (Omit the + sign in your answer.)

• A. 2
• B. 4
• C. 3
• D. 1

Answer: (C)

Verified step by step guidance

1. Identify the overall charge of the complex ion, which is given as 2- (written as \$2^-$).
2. Determine the charges of the ligands attached to the metal ion. Ammonia (NH\(_3\)) is a neutral ligand with a charge of 0, and bromide (Br\(^-\)) is an anionic ligand with a charge of -1.
3. Write an equation representing the sum of the charges: let the charge of the metal ion be \(x\). The total charge is the sum of the metal ion charge plus the charges of the ligands, which equals the overall charge of the complex.
4. Express this mathematically as: \(x + 2(0) + 4(-1) = -2\), simplifying to \(x - 4 = -2\).
5. Solve the equation for \(x\) to find the charge of the metal ion.