Assuming 3.0% hydrogen peroxide by weight has a density of 1.00 g/mL, demonstrate that an excess of hydrogen peroxide was used in the oxidation step...

Assuming 3.0% hydrogen peroxide by weight has a density of 1.00 g/mL, demonstrate that an excess of hydrogen peroxide was used in the oxidation step of Fe(II) to Fe(III). Think about redox balancing where you used half reactions to add up to get the final, overall reaction. What is the limiting reagent? Reaction is 2FeC2O4⋅2H2O(s) + H2O2 + 4C2O4 2- → 2[Fe(C2O4)3] 3- + 4H2O + 2OH, 20 mL of hydrogen peroxide was used.