Chemistry - Real Gas Question with Solution | TestHub

van der Waals equation for 1 mol of real gas is

$\left[\text{P}+\frac{\text{a}}{{\text{V}}^2}\right]\left[\text{V}-\text{b}\right]=\text{RT}$

Given that b = 0

$\therefore \left(\text{P}+\frac{\text{a}}{{\text{V}}^2}\right)\left(\text{V}\right)=\text{RT}$

$\therefore \text{PV}=\text{RT}-\frac{\text{a}}{\text{V}}$........ (i)

Following y = mx + c for the curve$\text{PV vs }\frac{1}{\text{V}}$

$\text{Slope}=-\text{a}$

$\text{Slope}=\frac{\text{21.6}-\text{20.1}}{2-3}=-\text{1.5}$

$\therefore \text{a}=\text{1.5}$