How does molecular weight affect diffusion?

1 Answer
Jun 15, 2017

More molecular weight means


Thomas Graham, founder of Graham's Law of Diffusion, concluded that chemical has less molecular weight diffuse faster.

As a proof for Graham's idea NH3 and HCL tube reaction can be used.

Molecular weight of ammonia = 17 g/mol
Molecular weight of hydochloric acid = 36.5 g/mol

Ring of NH4Cl is formed near to HCl beacuse NH3 diffused faster however HCl is diffused slower because of its high molar mass.