To and fro movement of liquid molecules from an interface in a confined space as a closed surrounding [ See the Explanation Below ]
Explanation: The above animation shows that the liquid particles(shown by blue circles) inside a closed container continuously enter in the vapour phase(shown by yellow circles) and simultanoeusly the particles in vapour phase enter into the liquid phase.Initially the rate of change of phase from liquid to vapour is greater than that of from vapour to liquid.This rate gradually increases and after sometime an equilibrium is attained in which the rate of change of phase from vapour to liquid and vice versa are same.
