the stoic ratio in rxn 2 is 6:2 So first you multiply 0.01202 by 6. Then divide that by 3 to give you the number of moles for Fe(OH)3 + 6H2O which gives you 0.0204 mol. then you use that to find the grams which you dont really need, i think. For the third rxn the ration is now 2;2 or 1:1. So what I did is divide 0.0204 mol by 2 and that gives u the number of moles for the iron complex = 0.0102 mol * 491.1 g/mol which gives a mass of 5.009 g.