Question

Assertion: Water kept in an earthen pot becomes cooler during summers.
Reason: Earthen pots have small pores through which water seeps via evaporation taking latent heat. Removal of latent heat results in cooling of water.
(i) Both assertion and reason are correct and reason is the correct explanation of the assertion.
(ii) Both assertion and reason are correct but reason is not the correct explanation for the assertion.
(iii) Assertion is correct but reason is incorrect.
(iv) Both assertion and reason are incorrect.

Answer 1

Hint: Take into consideration whether any capillary action can occur inside the earthen pot. Also try to think in terms of the process of evaporation, how it can occur what consequences can be seen if the process occurs. Then try to find out whether the reason established is true for the assertion given.

Complete step-by-step answer:
Capillary action is the ability of a liquid to flow in narrow spaces without any assistance or opposition of external.
While evaporation is a type of vapourisation on the liquid surface as it changes from liquid to gas phase taking the latent heat from the liquid.
Now the earthen pots are made such that they have a large number of extremely small pores on them. Water seeps out through these pores by the process of evaporation taking the latent heat required for evaporation from the earthen pot and the water present inside it. The earthen pot and water loses their heat , thus making the water present inside the earthen pot cool.
For evaporative cooling to work, the air needs to be dry so that more molecules leave the water than condense into it because a reverse process can occur on a wet day when water molecules in the air can rejoin the water on the pot walls, and if the air is hot then during this process will heat the pot and the water.
For the process to occur the air needs to be dry and hence can take place during summer.
So in the given question both assertion and reason are correct and the reason is the correct explanation to the assertion.

Hence the correct answer is option (i) .

Note: You must read the assertion and reason with proper attention and try to understand them as sometimes they may be confusing leading to silly mistakes. Also make sure to read the options correctly as in many cases students make mistakes by marking wrong options in spite of knowing the correct answer.