Question

At low pressures (for 1 mole), the van der Waal's equation is written as:
$[p+\frac{a}{V^2}]V=RT$
The compressibility factor is then equal to :

• A. $(1-\frac{a}{RTV})$
• B. $(1-\frac{RTV}{a})$
• C. $(1+\frac{a}{RTV})$
• D. $(1+\frac{RTV}{a})$

Answer 1

The correct option is A $(1-\frac{a}{RTV})$

Compressibility factor is $Z=\frac{PV}{RT}$

From the van der Waal's equation : $\frac{PV}{RT}=(1-\frac{a}{RTV})$