How can we explain the transitions of a substance from a liquid to a gaseous state and from a gaseous to a liquid state
How can we explain the transitions of a substance from a liquid to a gaseous state and from a gaseous to a liquid state from the standpoint of the molecular-kinetic theory?
The temperature of a liquid, like a solid or gaseous body, is related to the average kinetic energy of the movement of molecules. The higher the average kinetic energy of the molecules, the higher the temperature of the liquid. Individual molecules of a liquid can have such kinetic energy that they will be able to do work against the forces of attraction of molecules in the liquid, as well as against the external pressure of the already formed vapor, that is, they can leave the liquid. Simultaneously with the transition of molecules from liquid to vapor, the reverse process occurs. Moving randomly over the surface of the liquid and colliding with air molecules and among themselves, some of the molecules return to it again.