Molecular Explanation of Evaporation

Each of the molecules of a liquid does not have the same temperature and energy but the liquid as a whole has its average temperature. The molecules with high energy tends to escape through the surface of the liquid . when this happen through evaporation the resultant energy of the remaining molecules  become lower  than the previous value. This resulted in a lower temperature of the liquid.

The human body utilises the process of evaporation for cooling . if we become too hot through exercises or due to hot surroundings, we sweat and the evaporation of the liquids from the skin cools the body.

The molecules in a solid are held together by intermolecular force. These molecules vibrate in their fixed position . As the temperature increases,  the vibration increases . at a certain temperature the molecules has enough energy to overcome the force binding them and start to melt, because they now have enough energy to move free.

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