Give reason for the increase in rate of evaporation of a liquid when:

(a) air is blown above the liquid.

(b) surface area of liquid is increased.

(c) temperature of liquid is increased.

(a) Blowing air above the surface of liquid takes away the molecules escaping from liquid surface and to take their place other molecules move to the surface of liquid thus increasing evaporation rate.

(b) On increasing the surface area of the liquid, number of molecules escaping out of the surface increases. This increases the rate of evaporation.

(c) Energy of molecules increases with increase in temperature. So more and more molecules come to the surface of the liquid and escape out. Hence, rate of evaporation increases with increase in temperature.