What is the measure of the average kinetic energies of all the molecules in substance?

Kinetic theory of gases is a description of gas as a large number of non-stop random moving particles (atoms or molecules, generally without distinction in physics, are called molecules). Fast-moving molecules continuously collide with other molecules or the walls of the container. Molecular motion theory is to explain the macroscopic properties of gas, such as pressure, temperature, volume, etc., through the composition and motion of molecules. The theory of molecular motion believes that pressure does not come from static repulsion between molecules, as Newton’s conjecture, but from collisions between molecules that move thermally at different speeds.

The molecule is too small to be seen directly. The random movement of pollen particles or dust particles under the microscope-Brownian motion, is a direct result of molecular collisions. This can be used as evidence of the existence of the molecule.

Temperature is a measure of the average kinetic energy of the particles in a substance. Temperature of a volume of air represents the average kinetic energy of its molecules. Temperature is a measure of the average kinetic energy of a substance.

According to Kinetic Molecular Theory, the average kinetic energy of gas molecules is a function only of temperature. where T is the Kelvin temperature and k is Boltzmann's constant.