Assertion: For a real gas, the gas pressure is always less than the pressure calculated from kinetic theory of gases. Reason: In kinetic theory, both molecular volumes and intermolecular attractions were ignored.

It was observed that there is some amount of intermolecular force of attraction, between the gas molecules namely the van der waal forces. This doesn't let the molecules hit the wall of the container with full force as it is held back by attractive forces. Due to the force of attraction, real gasses tend to show slightly lower pressure as compared to ideal gasses.