Question

If helium and methane are allowed to diffuse out of the container under similar conditions of temperature and pressure,then the ratio of rate of diffusion of helium to methane is:

• A. $1:2$
• B. $2:1$
• C. $1:4$
• D. $4:1$

Answer 1

The correct option is B $2:1$

Acording to grahams law of diffusion,
rate of diffution is proportional to $\frac{\text{1}}{\text{(}\sqrt{M})}$
Where, $M$ is the molar mass of the gas
$\frac{\text{Rate of diffusion of helium}}{\text{Rate of diffusion of methane}}=\frac{\text{(}\sqrt{16})}{\text{(}\sqrt{4})}=2:1$