Question

Why real gases deviate from ideal behaviour in short ans?

Answer 1

The behavior of real gases usually agrees with the predictions of the ideal gasequation to within 5% at normal temperatures and pressures. At low temperatures or high pressures, real gases deviate significantly from ideal gas behavior. ... It also assumes that the force of attraction between gas molecules is zero.

Answer 2

Causes

1. one of the posulates of kinetic molecular theory of gasses is there are no attractive or repulsive forces among gas molecules.

this statement is not true, under high pressure and low temprature because, under these conditions the volume of gas is very very small and the distance between the molecules are also very small, as a result intermolecular forces develope which cannot be neglected. because of these intermolecular forces, the observed pressure is always smaller than that of ideal gas

2. One of the posulates of kinetic molecular theory of gasses is, the actual volume occupied by gas molecules is negligible when compared to the total volume of the gas. This statement is not true at higher pressure and lower temperature because at these conditions, the volume of gas is extremely small.