Question

3)Comment on the following statements:

i)Rate of evaporation of an aqueous solution decreases with increase in humidity.

ii)The water kept in an earthen pot(matka) become cool during summer.


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Answer 1

i)If humidity is high, then air is already saturated with water vapours, i.e., it has a lot of water vapours. Therefore, it will not take more water vapours easily. Hence, rate of evaporation decreases

ii)An earthen pot or a matka is porous in nature. Water placed in earthen pots is evaporated from minuscule pores it has as it is made of mud particles. This evaporation of water produces a cooling effect. ... Hence, water storedin earthen pots tends to become cooler in summer.

Answer 2

Answer:

1) The rate of evaporation of water depends on humidity. If humidity is more than the rate of evaporation is less. See, humidity can be roughly understood as the amount of moisture present in the air. If the air already has enough moisture it doesn't need more so the rate of evaporation becomes less. Thus, rate of evaporation of an aqueous solution decreases with the increase of humidity.

2) Actually, the earthen pots have a large surface area which allows evaporation to take place. Evaporation causes cooling. Hence, water kept in matkas become cool during summer.( Note- The rate of evaporation during summer is more as the humidity is less)