Question

why is rain water called as purest water

Answer 1

it is called as purest water becoz many impurities like SO2 and NO2 and many more harmful substances are mix in it and this water is not fit for houseuses. hope it will help you

Answer 2

It is because when water becomes water vapor through evaporation it leaves behind all of its impurities.This beater condenses and falls down as rain .this is why rainwater is the purest form of water.
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