Which condition out of the following will increase the evaporation of water? (a) Increase in temperature of water (b) Decrease in temperature of water (c) Less exposed surface area of water Adding common salt to water
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Answer is a) Increase in temperature of water Explanation:
Increase in temperature of water increase the kinetic energy of the water which will make more particles to attain enough energy to convert into vapour state. This is how increase in temperature favours evaporation.
On the other hand exposed surface is also responsible for the evaporation. Higher the exposed surface are higher will be the evaporation.
When common salt is added to water then surface is occupied by the solvent as well as non-volatile solute particles.
This make the escaping tendency of solvent particles decrease and thus the evaporation of water decreases. Hence options (b), (c) and (d) will decrease the evaporation of water.
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