Question

Give reason why real gases deviates from ideal behaviour

Answer 1

Real gases deviate from ideal behaviour because their particles(atoms for inert gases or molecules) occupy some finite space and do exert interactive forces among them. Complete Ideal behaviour is hypothetical because of the reasons above, At low temperature and high pressure real gases behave approximately as ideal gases. In ideal behaviour gas particles don't occupy space and do not have any interaction, as assumed in kinetic theory of gases. But in reality this is not the case so we would get error on applying gas law so Van der waal , corrected it by introducing suitable constants.

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 temprature because at these conditions, the volume of gas is extremely small.