We will analyse the behavior of an ideal gas from the molecular level. The kinetic molecular theory represents a microscopic model for different gases since it throws a light on the behaviour of the particles which constitute the gas. This kinetic modelling (KINETIC MOLECULAR THEORY OF GASES) is done based on the following postulates for a gas:

1.    A gas consists of tiny particles, either atoms or molecules, moving at random

2.    The volume of particles themselves is negligible when compared with the total volume of the container or the gas as stated earlier

3.    There are no interactions between the particles of the gas

4.    Collisions with walls and among themselves are elastic that is the total kinetic energy at a given temperature is constant.

5.    The laws of classical mechanics are applicable on the motion that is when the molecules of the gas collide with the walls there is a change in momentum and hence a force is applied which appears as the pressure of the gas.

Kinetic theory of gases allows us to derive theoretically, all the gas laws studied in the previous sections. Calculations and predictions based on kinetic theory of gases agree very well with the experimental observations and thus establish the correctness of this model.

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