Question

What are the values of the critical constants Vc , Tc and Pc ? Hence, show that the value of the critical coefficient is
8/3.

Answer 1

The values of the critical constants:

$$T_c=\frac{8a}{27Rb}$$

$$P_c=\frac{a}{27b^2}$$

$$V_c=3b$$

The value of the critical coefficient is  

$$\frac{RT_c}{P_cV_c}=\frac{R(\frac{8a}{27Rb})}{(\frac{a}{27b^2})3b}=\frac{8}{3}$$