Question

why water has no colour?

Answer 1

While relatively small quantities ofwater appear to be colorless, water'stint becomes a deeper blue as the thickness of the observed sample increases. The blue hue of water is an intrinsic property and is caused by selective absorption and scattering of white light

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Answer 2

When water is in small quantities (e.g. in a glass) it appears colorless to the human eye

While relatively small quantities of water appear to be colorless, water's tint becomes a deeper blue as the thickness of the observed sample increases. The blue hue of water is an intrinsic property and is caused by the selective absorption and scattering of white light. Impurities dissolved or suspended in water may give water different colored appearances.