Calcium sulfide reacts with calcium sulfate as shown.
CaS + 3 CaSO4 → 4 CaO + 4 SO2
2.50 g of calcium sulfide are heated with 9.85 g of calcium sulfate until there is no further reaction.
Show that calcium sulfate is the limiting reagent in this reaction.
Calculate the mass, in g, of sulfur dioxide formed.
Mr (CaS) = 72.2
Mr (CaSO4) = 136.2
answer is 6.18g.
the mark scheme says this "3 mol of CaSO4 needed for each mol of CaS, and n(CaSO4) is not 3 × n(CaO) (so CaSO4 is the limiting reagent)" which i dont get bc i thought CaS was the limiting reagent bc it's amount is less when we calculate.