Question

A gas cylinder is filled with helium at 2000 mm. Due to leakage, the pressure dropped to 1500 torr in 40 min. When the same cylinder is filled with another gas at the same pressure, the pressure dropped from 2000 mm to 1500 mm in 200 min. What is the molecular weight of the gas?

Answer 1

(i) relation between drop in pressure and rate of diffusion
(ii) relation between the rate of diffusion and molecular weight of gases
(iii) 100