What is latent heat of fusion?

Latent heat of fusion is the amount of heat energy required to change 1 kilogram of a solid into a liquid at its melting point without any change in temperature.

For example, ice at 0°C absorbs heat and melts into water at 0°C. During this process, the temperature remains constant even though heat is being absorbed.

For water, the latent heat of fusion is 3.34 × 10⁵ J/kg (or 334,000 J/kg).

In simple terms, it is the hidden heat needed to convert a solid into a liquid without raising its temperature.