12. Solution to Chemistry Problem

2. In a 1.175 g sample of steel, chromium was oxidized to Cr2O42-. Then 25.0 ml of FeSO4 solution were added in excess and its unreacted residue was titrated with 3.7 ml of KMnO4 solution. It is known that T(KMnO4) = 0.000710 g/ml, and that 25 ml of FeSO4 solution are equivalent to 25.82 ml of KMnO4 solution.