Define the following terms:

a) melting point

b) boiling point

c) evaporation

(a) Melting Point:

Temperature at which solid starts to melt. Melting point is the temperature at which solid and liquid state exists in Equilibrium. This process is called melting.

(b) Boiling Point:

Temperature at which liquid starts to boil at atmospheric pressure. Vapor pressure of liquid equal to the atmospheric pressure. This process is known as boiling.

(c) Evaporation:

Evaporation is the process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure. It is Surface phenomenon Liquid molecules collide each other and transfer energy to each other, When Liquid molecule at surface absorbs enough energy to overcome the vapor pressure.

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