3. o Description of Evaporation
o Factors Effecting Evaporation
o Advantages of Evaporation

4. What is Evaporation?
When a liquid is left exposed to air. Its
volume decreases gradually. This is due to
evaporation. In this process some of the
liquid at the surface turns into vapour
and mixes with the gases in the
atmosphere. Thus, when a liquid turns
into vapour, it is said to evaporate.
So, the process of a liquid changing into vapour even
below its boiling point is called EVAPORATION.

5. Factors affecting Evaporation
There are 4 factors
affecting Evaporation:  Temperature
 Surface Area of the
Liquid
 Humidity of Air
 Wind Speed

6. Factors affecting Evaporation
O Temperature :- The rate of evaporation increases
on increasing the temperature of the liquid.
O Surface Area of the Liquid :- The rate of
evaporation increases on increasing the surface
area of the liquid.
O Humidity of Air :- When the rate of humidity is
low, then the rate of evaporation is high and when
the rate of humidity is high, then the rate of
evaporation is low.
O Wind Speed :- The rate of evaporation of a
liquid increases with the increasing wind speed.

7. Advantages of Evaporation
O Evaporation brings rain.
O Evaporation cools the water kept in earthen pot.
O By the help of evaporation, water cycle goes on.
O Purification of water is done by evaporation.
O Salt is obtained by evaporation.
O Clothes get dried up by evaporation.