Molecules in a liquid are in constant motion, which is an expression of their thermal energy, is a kinetic theory.
Properties of kinetic theory:
The particles seem to be in continual random motion, colliding with the container's walls. The pressure produced by the gas is caused by collisions with the walls. Because the pressure in a container remains constant throughout time, molecular collisions have been believed to be completely elastic.
Gases are made up of particles that are insignificant in comparison to their container and the space between them.
The average kinetic energy of such a system's molecules is related to the absolute Kelvins.
It is believed that the gas particles do neither interact nor repel one other.