Question

The average molar mass of components of air mainly diatomic gas and diatomic oxygen gas is about 29g/mol what is the volume of 1kg of air at atmospheric pressure and 20C

Answer 1

According to the Ideal Gas Law, the volume of one mole of gas is

$$V=\frac{nRT}{p}=\frac{1\cdot8.314\cdot(273+20)}{101325}=24\cdot10^{-3}\text{ m}^3.$$

Therefore, the volume of gas does not depend on its molar mass.