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

Boltzman Distribution. The behavior of the gas molecules under the action of gravity. Concentration of the molecules are maximal at the bottom of vessel and it diminishes with the height exponentially.

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

Thermal oscillation of a piston in the presence of gas. The mean kinetic energy of a piston equals kT/2. It is the same as the mean kinetic energy of any molecule in a gas associated to each degree of freedom.

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

Separation of isotopes by method of isothermal effusion. On the left side of the vessel there is a mixture of two types of particles that differ by mass 25 times. The velocity of the light particles (red color) is 5 times greater than the velocity of the heavy particles (blue). As a result the light particles will diffuse into the right side of the vessel more rapidly than the heavy particles.

Molecular structures: CAFFEINE (C₈H₁₀N₄O₂) and ETHANOL (C₂H₅OH).

The surplus positive charge of the Earth's surface is cancelled out by the flow of negative electrons from the clouds. We can see this discharge in the form of lightning bolts.