Question

The amount of heat energy required to change 1 kg of solid into liquid at its melting point is known as ______________

• A. crystallisation
• B. latent heat of fusion
• C. latent heat of vapourisation
• D. sublimation

Answer 1

The correct option is B

latent heat of fusion

The amount of heat energy required to change 1 kg of solid into liquid at its melting point is known as latent heat of fusion. Latent heat of fusion is the reason why ice at $0^{\circ }C$ doesn't instantly turn into water! Even after reaching a temperature of $0^{\circ }C$, some extra energy is required to convert ice to water.

The latent heat of fusion of water at $0^{\circ }C$ is 334 joules/ kg. 334 joules is the extra energy required after reaching $0^{\circ }C$.