What is the charge on the iron(III) complex ion in [Fe(OH)2(H2O)4]Br?

The charge on the iron(III) complex ion in [Fe(OH)2(H2O)4]Br can be determined by looking at the charge of the counter ion, which is bromide (Br-).

1. First, identify the charge of the bromide ion. The bromide ion (Br-) has a charge of -1.

2. The overall charge of the complex ion must balance with the charge of the counter ion. Since the bromide ion has a charge of -1, the complex ion must have a charge of +1 to balance it out.

3. However, we know that iron(III) has a charge of +3. This means that the other ligands in the complex ion must have a total charge of -2 to balance out the +3 charge from the iron.

4. The hydroxide ion (OH-) has a charge of -1, and there are two of them in the complex ion, contributing a total charge of -2. The water molecules (H2O) are neutral and do not contribute to the overall charge.

5. Therefore, the charge on the iron(III) complex ion in [Fe(OH)2(H2O)4]Br is +1.