What are the sources of water in nature? Name the purest and the most impure source giving a reason. - Question & Answer Book

Answer. The source of natural water are: 

Rainwater, groundwater of surface water, underground water, and seawater.

Rainwater is the purest form of natural water because it is obtained by the natural distillation (evaporation & condensation) of surface/seawater. The most impure form is sea water which contains the maximum amount of dissolved impurities from the earth’s surface. 

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