Graham’s Law of Diffusion

Graham’s Law of Diffusion states that provided the temperature and pressure are constant, that the rate of diffusion of gas is inversely proportional to the square root of its density.

R ∝ 1/√e

R₁R₂  = √(e₂/e₁)

Since relative molecular mass = 2 x density

i.e M = 2e

R₁R₂  = √(M₂/M₁)