What is the concentration of ferrous sulfate if 18 ml of 0.1 M potassium permanganate is needed to oxidize 25 ml of ferrous sulfate solution?

Answer 1

10FeSO4 + 2KMnO4 + 8H2SO4 = 5Fe2(SO4)3 + 2MnSO4 + K2SO4 + 8H2O

mol KMnO4 = (18/1000 L) (0.1 mol/L) = 0.0018 mol KMnO4

mol FeSO4 = (0.0018 mol KMnO4/1) (10 mol FeSO4 / 2 mol KMnO4) = 0.009 mol FeSO4

molarity FeSO4 = mol FeSO4 / L FeSO4

M FeSO4 = (0.009 mol / (25/1000 L))=0.36 M