Hydrosphere Contents

2. Properties Of Water

Melting and boiling point

Water has unusually high melting (0°C) and boiling (100°C) points compared to other molecules. This is because the bonds between the hydrogen atoms and oxygen atom must be broken in order for a phase transition to occur. The extra energy required means that more heat energy must be supplied. Because of these high melting and boiling points, water can remain as a liquid over much of the surface of the Earth. This allows it to be in the form necessary for it to act as a universal solvent and life giving fluid. This in turn means that water based organisms can colonise the whole planet, from the hottest deserts to the polar wastelands.

Water can be found almost everywhere allowing life to persist.

What is significant about the high melting and boiling points of water?