The iron content of hemoglobin is determined by destroying the hemoglobin molecule and producing small water-soluble ions and molecules. The iron in the aqueous solution is reduced to iron(II) ions and then titrated against potassium permanganate. In the titration, iron(II) is oxidized to iron(III), and permanganate is reduced to manganese(II) ions. A 5.00-g sample of hemoglobin requires 28.2 mL of a 0.002400 M solution of potassium permanganate. What is the mass percent of iron in hemoglobin? Mass percent = %