Question

158 grams of potassium permanganate is reacted with ferrous sulfide in the presence of hydrochloric acid, approximately how much ferric sulfate will it produce?

(a) 111 grams

(b) 169 grams

(c) 254 grams

(d) 399 grams

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This is a very interesting question from Stoichiometry topic in chapter The Chemical Reaction Equation & Stoichometry, Material Balances for Processes Involving Reaction and Multiple Units of Basic Chemical Engineering

Answer 1

Right choice is (a) 111 grams

For explanation: The balanced chemical reaction is 18KMnO4 + 10FeS + 32H2SO4 -> 18MnSO4 + 5Fe2(SO4)3 + 9K2SO4 + 32H2O, => weight of ferric sulfate = (158/158)*(5/18)*400 = 111.1 grams ≈ 111 grams.