Question

How would you confirm that a colourless liquid give to you is pure water?

Answer 1

By checking it's boiling point .If it starts boiling exactly at 100 ºthen it is pure water.

Answer 2

By finding the boiling point of a given colourless liquid. If the liquid boils at 100°C at atmospheric pressure, then it is pure water. This is because pure substances have fixed melting and boiling point.