This animation illustrates the concept of free path length of molecules in a gas.

Brownian motion. Chaotic motion of minute particle suspended in a gas or liquid.

Boltzman Distribution. The behaviour of the gas molecules under the action of gravity.

Compression and expansion of adiabatically isolated gas is accompanied by its heating and cooling.

Thermal oscillation of a piston in the presence of gas.

Maxwell Distribution. Experiment with Galton board demonstrates the statistical sense of Maxwell distribution.

Molecular structures.