Mass question? 10 points WILL be rewaded!!?

Question

Pyrite (FeS2) reacts with oxygen to produce magnetite (Fe3O4) and sulphur dioxide gas according to the following equation.

3FeS2 + 8O2----> Fe3O4 + 6SO2

a) Calculate the mass of O2, which would be required to react with 24.0 g of FeS2

b) Calculate the mass of SO2 which would be produced

Answer 1

24 g of Fe2S are 0,27 moles.

3 parts of it react with 8 parts of O2. So mass of O2 required is 32*8/3 g.

6 parts of SO2 are formed. That is 64*6/3 g.

32 g =MW of O2. 64 g = MW of SO2.