An experiment was carried out to find the value of n in hydrated iron(II) ethanedioate, FeC₂O₄ n H₂O. 1.71 g of the compound was dissolved in deionised water and made up to 250 cm³ solution in a volumetric flask. When 25.0 cm³ of this solution was acidified using an excess of dilute sulfuric acid, it was found to react with 28.50 cm³ of 0.0200 mol dm⁻³ potassium manganate(VII).
a. Deduce the number of moles of MnO₄⁻ that react with one mole of FeC₂O₄ n H₂O. Remember that both the Fe²⁺ and C₂O₄²⁻ ions react.
b. Find the relative formula mass of hydrated iron(II) ethanedioate and the value of n.