Heat and Phase Change Energy

Heat and phase change energy explain why substances melt, freeze, boil, and condense. A solid turns into a liquid during melting, also called fusion. The reverse process is freezing. A liquid turns into a gas during evaporation. The reverse process is condensation.

Each substance changes phase at...

Primarily there are three different phases of matter: solid, liquid, and gas.

On changing the temperature, one state changes into another. This phenomenon is called phase change, which is reversible in nature.

On heating, a solid changes to liquid, this process is called melting, while vice-versa is called freezing.

The heat...