Question

Ratio of the rate of diffusion of $He$ to $H_2$ at $0^{o}C$ is same to the case:

• A. when temperature is changed to ${100}^{o}C$
• B. when $O_2$ and $C{H}_4$ are taken instead of $He$ and $H_2$
• C. when volume of the flask is double
• D. all of the above

Answer 1

The correct option is D all of the above

Hydrogen gas exists as a diatomic molecule $H_2$. However, helium gas exists as nonatomic $He$.

$\frac{r_{H_2}}{r_{He}}=\sqrt{\frac{M_{He}}{M_H}}$

$=\sqrt{\frac{4}{2}}=\sqrt{2}=1.4$

$\therefore r_{H_2}:r_{He}=1.4:1$.

It is same in case because in rate of diffusion only depends on molecular mass, and in all cases molecular mass is same