Question

The partial pressure of a gas X is given by two bar, where is the total pressure of the gaseous mixture in a cylinder is 10 bar. What is the mole fraction of the gas X in that mixture?

(a) 0.5

(b) 2

(c) 0.2

(d) 5

I had been asked this question in an interview.

This interesting question is from States of Matter in division States of Matter of Chemistry – Class 11

Answer 1

The correct choice is (c) 0.2

To explain I would say: The partial pressure of a gas equals the mole fraction of the gas in the gaseous mixture x the total pressure that is exerted by the gaseous mixture. So here 2 bar =  molar fraction x 10 bar, we get that the mole fraction is 2/10 = 0.2.