Question

For real gases the relation between p, V and T is given by van der Waals equation : $\bigg \lgroup p+\frac{an^{2}}{V^{2}}\bigg \rgroup (V-nb) = nRT$ where ‘a’ and ‘b’ are van der Waals constants, ‘nb’ is approximately equal to the total volume of the molecules of a gas. ‘a’ is the measure of magnitude of intermolecular attraction.
(i) Arrange the following gases in the increasing order of ‘b’. Give reason. $O_{2}$, $CO_{2}$, $H_{2}$, He.
(ii) Arrange the following gases in the decreasing order of magnitude of ‘a’. Give reason. $CH_{4}$, $O_{2}$, $H_{2}$.

Answer 1

1-o2 than co2 than H2
2- CH4 than O2 than H2