- When a solid melt, heat is absorbed but the temperature remains constant.
- When a liquid is boiling, heat is also absorbed but the temperature again remains constant.
- The heat absorbed or given out at constant temperature during the change of phase is known as latent heat.
- The heat energy that releases during condensation or boiling is called the latent heat of vaporization.
- The heat energy that releases during freezing or melting is called the latent heat of fusion.
The latent heat is the heat absorbed or given out at constant temperature during the change of state of matter.