Comment on the following statements :
$(a)$ Evaporation produces cooling.
$(b)$ Rate of evaporation of an aqueous solution decreases with increase in humidity.
$(c)$ Sponge though compressible is a solid.

(N/A) Evaporation produces cooling because the particles at the surface of the liquid gain energy from the surroundings to overcome the forces of attraction and change into vapour,thereby absorbing heat and producing a cooling effect.
$(b)$ Humidity is the amount of water vapour present in the air. Air can hold only a definite amount of water vapour at a given temperature. If the humidity is already high,the air cannot hold more water vapour,which decreases the rate of evaporation.
$(c)$ $A$ sponge has minute holes in which air is trapped. When we press it,the air is expelled out,allowing it to be compressed. Despite this,it is considered a solid because it has a definite shape and volume when not subjected to external force.