IMPORTANT POINTS

KINETIC MOLECULAR THEORY OF GASES

In order to explain the behaviour of gases, Bernoulli proposed kinetic molecular theory in 1738.  Later clauses deduced kinetic equation and explained all gas laws from it. After that Maxwell and Boldzmann discussed the distribution of velocities and energies and vanderwaal studied the physical behaviour of gases.

FUNDAMENTAL POSTULATES OF KMT

˜     All gases consist of tiny invisible particles called molecules (He, Ne, Ar are monoatomic).

˜     These molecules are in constant random motion in straight line until colliding with other molecules or with the wall of the container.

˜     The collisions of the molecules are perfectly elastic (there is no gain or loss of energy take place during collision).

˜     The collisions of the molecules with the wall of the container, gases exert pressure.

˜     The size of molecules is so small as compared to the volume of the gas.

˜     The molecules of a gas have no forces of attraction for each other.

˜     There is no effect of gravity on gas molecules.

˜     The average kinetic energy of a molecule of a gas is directly proportional to their absolute temperature.

˜     Clauses kinetic theory equation is PV = 1/3 mnĉ².