Mole Concept

1)When burnt in air,a 12.0 g mixture of carbon and sulphur yields a mixture of CO₂ and SO₂,in which the number of moles of SO₂ is half that of CO₂.The mass of the carbon the mixture contains is
(a)4.08g (b)5.14g (c)8.74g (d)1.54g(ANS-(b))
2)In an experiment,it is found that 2.0769g of pure X produces 3.6769g of pure X₂O₅.The number of moles of X is
(a)0.04 (b)0.06 (c)0.40 (d)0.02 (ANS-(a))