Changing States of Water

Water exists in three states

Water can changes its state when it becomes colder (loses heat) or hotter (gains heat)

When water loses heat or gains heat

When water is cooled to 0 °C, it changes to ice

Water changes from liquid to solid state

Freezing

loses heat

The freezing point of pure water is 0°C

When ice cube at 0 °C gains heat, it changes to the liquid state

Water changes from solid to liquid state

Melting

gains heat

Freezing

Melting

When we heat water to a temperature 100 °C, it changes the liquid water to steam

Water changes from liquid to gaseous state at 100 °C

Boiling

The boiling point of pure water is 100°C

When we heat water at temperature below its boiling point, the liquid water changes into water vapour

Water changes from liquid to gaseous state at temperature below 100 °C

Evaporation

gains heat

When water vapour and steam are cooled, it condense into liquid water

Water changes from gaseous to liquid state

Condensation

loses heat

How quickly or slowly evaporation takes place is known as the rate of evaporation

The rate of evaporation depends of: - wind - temperature difference - surface area

Condensation

Evaporation