how does evaporation cause cooling? Explain with example
Answers
first of all, what's evaporation?
evaporation is a simple process of vaporization where the liquid changes it's state to gaseous state.
evaporation causes cooling effect because during the process of evaporation, the particles of water (liquid) lose all their energy so the particles of water again absorb energy (heat) from surroundings lost during evaporation. because of the lose of heat in the surroundings, it makes it cool.
some examples are as follows :-
⏺we sprinkle water on an open ground or on any surface during summer because it makes the surrounding cool. as I said before the evaporation causes cooling effect and also how.. that's why people sprinkle water in a hot sunny day.
⏺we feel cool when we put some acetone on our palm. it's because of cooling effect of evaporation. the particles of acetone gain energy from surroundings and palm and then when it evaporates, it leave our palm cold.
⏺tea poured in a saucer cools faster as compared in the cup. as we know evaporation is a surface phenomenon. and when exposed to larger area, rate of evaporation increases and hence tea in the saucer cools faster.
⏺we feel cold when we sweat during summer. because the particles gain energy from our body and evaporates. as a result, we feel our body cold.
Evaporation is the process of a substance in a liquid state changing to gaseous state due to an increase in its temperature or you can say that it absorbs energy in tend to increase its temperature to evaporate.
◼ During the process of evaporation (liquid to gaseous) it absorbs all the heat from outer surface which makes the surface cool. Evaporation causes cooling naturally.
(OR)
◼ During the process of evaporation, the matters requires some energy to change its state from liquid to vapour. So it takes energy from the surrounding in the form of heat.
Now, let us take a very common example⬇
✴ We sweat during summers in order to cool our body temperature as water from our body evaporates by taking energy from our body and results in lowering the body temperature.
✴ Another common examples of evaporation are Acetone and Perfume.
In these cases the liquid evaporation is often quick as compared to water. When liquid evaporates they remove heat from the surface they are evaporating; in this case, from your skin. When perfume is applied on our body that liquid absorbs heat from your body and makes your body feel cool.
⭐ Note :- Acetone is the best example of evaporation cooling because acetone liquid gets evaporated much faster and makes the surface cool as compared to perfume or water.