Question

A mixture contains 20% CO2, 30% SO2 and 50% H2O, what is the mass percent of CO2?

(a) 23

(b) 45

(c) 66

(d) 87

I got this question during an interview.

This interesting question is from Analyses of Multicomponent Solutions and Mixtures topic in chapter Moles, Density & Concentration of Basic Chemical Engineering

Answer 1

Correct answer is (a) 23

The best explanation: Let the moles be 20, 30 and 50, => mass percent of CO2 = (20*44)/[20*44 + 30*64 + 50*18] = 23%.