Question

State any ‘four’ assumptions of kinetic theory of gases.

Answer 1

Hint The kinetic theory of gases is a theory with simplified assumptions regarding the nature of gas, like the presence of similar particles in a gas which can be used to derive the collective /gross properties of gas like pressure on the walls of the container, density, viscosity, thermal and electrical conductivity, etc.

Complete Step by step solution
Four assumptions of the kinetic theory of gases are-
1. The gas is composed of a large number of tiny molecules, which are identical in shape, size, and properties.
2. The molecules are separated from each other by a very large and random distance.
3. The molecules are rigid and undergo perfectly elastic collisions but otherwise, they do not interact with each other.
4. The transfer of kinetic energy between the gas molecules takes place in the form of heat.
The kinetic theory had other assumptions as well, like-
1. -At the same temperature, the kinetic energy of all molecules is the same.
2. -The volume of all the molecules combined is very less than the actual volume occupied by the gas.

Additional information
The kinetic molecular theory or the kinetic theory of gases can define the collective properties of gases to a high accuracy when a gas behaves like an ‘ideal gas’ which follows the above assumptions. But, at high densities, where the van der waals forces come into action, or when different types of gases are mixed, the properties change and they could deviate positively or negatively from the curves plotted for the ideal gas.

Note The kinetic theory of gases is used to define the bulk properties of a gas, therefore it does not define the individual property of the molecules, like its spin or its kinetic energy. But the average kinetic energy of the molecules collectively can be defined by its temperature.