Question

Positive deviation from ideal behaviour takes place because of :

• A. molecular interaction between atoms and $\frac{PV}{nRT}>1$
• B. molecular interaction between atoms and $\frac{PV}{nRT}<1$
• C. finite size of atoms and $\frac{PV}{nRT}>1$
• D. finite size of atoms and $\frac{PV}{nRT}<1$

Answer 1

The correct option is A molecular interaction between atoms and $\frac{PV}{nRT}>1$

A gas shows a positive deviation from ideal behaviour if there is a force between the molecules and repulsive force dominates over attractive force. For such gases the compressibility factor $z$ is more than 1 or $z=\frac{PV}{nRT}>1$.