Is the cation in Mn2S3 manganese II or manganese III? Explain.

The cation in Mn₂S₃ is manganese III.

To understand why, we need to look at the oxidation states of the elements involved. In the compound Mn₂S₃, we have two manganese (Mn) ions and three sulfide (S) ions. Sulfur typically has an oxidation state of -2. Since there are three sulfur ions, the total negative charge contributed by sulfur is:

• 3 (sulfide) × -2 (charge per sulfide) = -6

To balance this -6 charge, the manganese ions must collectively have a +6 charge. Since there are two manganese ions, each must have an oxidation state of +3 to achieve this balance:

• 2 (manganese) × +3 (charge per manganese) = +6

This confirms that in Mn₂S₃, each manganese ion is in the +3 oxidation state, indicating that the cation is manganese III.