The amount of iron in an iron ore is determined by converting the Fe to FeSO₄, followed by a titration with a solution of
K₂Cr₂O₇.
a. What is the molarity of Fe²⁺ 21.85mL of 0.250M K₂Cr₂O₇ is required for the titration of 30.0 mL of FeSO₄ solutions?
b. If the original sample of iron ore had a mass of 2.58 g, what is the mass percent of iron in the ore?