Question

sulphur trioxide is prepared by the following two reactions :
S8(s) + 8O2(g) --> 8SO2(g)
2SO2(g) + O2(g) --> 2SO3(g)
How Many grams of SO3 are produced from one mole of S8?

Answer 1

           S8 + 802 --> 8SO2
SC ....1*32  8*32     8*64
           2SO2 + O2 --> 2SO3
SC.....2*64      1*32      2*80
Now, S8 produces 8*SO2
so 2SO2 produces 2SO3
Hence 8SO2 will produce 8SO3
Hence 640g of SO3 will be produced from 1 mole S8