By Sunil Bhardwaj


This theory makes the following assumptions :

(1) Every gas is made up of a large number of extremely small particles called molecules. All the molecules of a pafticular gas are identical in mass and size and differ from gas to gas.

(2) The molecules of a gas are separated from each other by large distances so that the actual volume of the molecules is negligible as compared to the total volume of the gas.

(3) The distances of separation between the molecules are so large that the forces of attraction or repulsion between them are negligible.

(4) The molecules are supposed to be moving continuously in different directions with velocities Hence, they keep on colliding with one another (called molecular as well as on the walls of the containing vessel.

(5) The pressure exerted on the walls of the containing vessel is due to the the molecules on the walls of the containing vessel.

(6) Since the molecules are moving with different velocities, they possess differem energies. However, the average kinetic energy of the molecules of a gas is proportional to the absolute temperature of the gas.

(7) Molecules are supposed to be perfectly elastic hard spheres so that no energy is lost when the molecules collide with one another or with the walls of the vessel.

(8) The force of gravitation on the molecules is also supposed to be negligible.