Evaporation causes cooling. Explain why?

Explanation

Evaporation is the process in which molecules on the surface of liquid go into the vapour phase. Only those molecules will leave the surface which have higher kinetic energy. Molecules having less kinetic energy remain in liquid phase. If no heat is supplied from the outside source, then average kinetic energy of molecules in liquid plase decreases. Because K.E.`prop`T, therefore, temperature of liquid gets lowered.