Question

The value of b for carbon dioxide is given as 42.69 x 10^-6m^3/mol. What do you think is the volume of a molecule?

(a) 7.59 m^3

(b) 7.03 m^3

(c) 76.09 m^3

(d) 7.09 m^3

I had been asked this question in an international level competition.

Question is taken from States of Matter in portion States of Matter of Chemistry – Class 11

Answer 1

Correct option is (d) 7.09 m^3

The best I can explain: From van der Waal’s equation (P – an^2/V^2)(V – nb) = nRT, we know that V = b/NA = 42.69 x 10^-6m^3/mol/6.023 x 1023 molecules/mol. That equals 7.09 m^3/molecule. So the volume of a molecule is 7.09m^3.