Question

What is evaporation? State the various factors which affect evaporation.
​(b) Why does evaporation cool a liquid?

Answer 1

(a) The phenomenon of conversion of a liquid into its vapors at any temperature below its boiling point is known as evaporation.
Various factors which affect evaporation are:

(i) Velocity of wind
(ii) Humidity
(iii) Surface area
(iv) Temperature

(b) As we know that when a liquid evaporates it converts into liquid before its boiling point, so when it evaporates the particles at the surface of the liquid uses the heat of the liquid as energy to increase the kinetic energy so that they are able to overcome the force of attraction of the other particles of liquid and then directly convert into the gaseous state. That's why the temperature of the liquid gets reduced and it becomes cooler.