Explain what is the percent purity of a sample of impure H2C2O4• 2H2O (oxalic acid dehydrate, 126.07 g/mol) if 0.9157 grams of this material require a titration with 27.67mL of a potassium permanganate solution? The titrant contains 5.980 mg of potassium permanganate (158.04 g/mol) per 1.000mL of solution. Oxalate is oxidized as well as permanganate is reduced. State the balanced chemical equation in net ionic form.