Question

Calculate the ratio of the rate of diffusion of oxygen to the rate of diffusion of hydrogen at constant temperature and pressure.

Answer 1

From Graham's law of diffusion

$r\propto \frac{1}{m}$

$\Rightarrow \frac{r_{O_2}}{r_{H_2}}=\sqrt{\frac{M_{H_2}}{M_{O_2}}}$

$\frac{r_{O_2}}{r_{H_2}}=\sqrt{\frac{2}{32}}=\frac{1}{4}$