the conversion of liquid to vapours is a change in state of a system from one state to other
there are basic two differences between three states of matter
1. thermal energy: gas has highest thermal energy tthen liquid and least us of solids
2. intermolecular forces of attractions
solids have highest intermolecular forces of attraction , then liquid and least in gas
sovas we increase the temperature the forces if attraction decrease s and thermal energy increases.
So when we heat liquid more moleculws gets energised attaining thermal motion in the range of gas thus the rate if evaporation increases.