Question

Mean free path increases if:

• A. $H_2$ is replaced by $He$
• B. $He$ is replaced by $H_2$
• C. $He$ is replaced by $O_2$
• D. $O_2$ is replaced by $C{O}_2$

Answer 1

The correct option is A $H_2$ is replaced by $He$

In case of mean free path as gas density of molecule becomes close to each other they are free to like each other and as decreasing the volume, density of molecule increases which decrease the mean free path.So when $H_2$ is replaced by $He$ mean free path increases.