Question

A mixture of gases SO2, O2 and 4 g of N2 and total mass of mixture is 10 g, what is the sum of mole fraction of SO2 and O2?

(a) 0.25

(b) 0.5

(c) 0.75

(d) 1

I got this question during an interview.

The query is from Mole Fraction and Mass(Weight) Fraction in division Moles, Density & Concentration of Basic Chemical Engineering

Answer 1

The correct choice is (c) 0.75

For explanation I would say: Sum of the mole fraction of all gases = 1, => sum of mole fraction of SO2 and O2 = 1 – 4/10 = 0.75.