[Viral]

If the mineral Pyrite, FeS2 is heated strongly in air, iron(III) oxide and sulphur dioxide are produced. What mass of

(a). Iron (III) oxide, and
(b). Sulphur dioxide could be made by heating 1 tonne of an ore which contained 50% by mass of pyrite?

4FeS2 + 11O2 --->  2Fe2O3 + 8SO2

(O = 16, S = 32, Fe = 56)

Please help.

[sjb]

50% of 1 tonne is what mass? Which is how many moles of pyrite?