A potassium permanganate solution containing 1.58g of KMnO4 per liter is added into 5 ml of an acidified iron (||) sulfate solution. Decolorizing of KMnO4 solution has been added .Calculate the mass of FeSo4.7H2O which has been dissolved in one liter of solution.

2 answers

mols KMnO4 = grams/molar mass
M = mols/L.
5Fe^2+ + MnO4^- ==> 5Fe^3+ + Mn^2+

mols KMnO4 used = M x L. You don't show L KMnO4. Without that you can't finish the problem.
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