Question

If the mole fraction of SO2 in H2SO4 is 0.2, what is the ratio of mass of sulfur and oxygen in the solution?

(a) 0.166

(b) 6

(c) 1.8

(d) 0.555

This question was addressed to me in class test.

Question is from Mole Fraction and Mass(Weight) Fraction topic in portion Moles, Density & Concentration of Basic Chemical Engineering

Answer 1

The correct option is (d) 0.555

The best I can explain: Let moles of SO2 and H2SO4 be x and y respectively, => x/(x + y) = 0.2, => y/x = 4, => ratio of mass of sulfur and oxygen in solution = (x*32 + y*32)/ (x*2(16) + y*4(16)) = 0.555.