What does the specific latent heat of fusion refer to?

The specific latent heat of fusion is defined as the amount of energy required to melt a unit mass (typically 1 kg) of a solid into a liquid at a constant temperature. This process occurs at the substance's melting point, where the temperature remains the same while the change of state from solid to liquid takes place.

In this context, melting involves overcoming the attractive forces between the particles in the solid state, allowing them to move freely and form a liquid. The energy absorbed during this phase change is used to break these intermolecular bonds rather than to increase the temperature of the substance, which is why it is referred to as latent heat.

This concept highlights the importance of energy transfer in phase changes and underlines how temperature remains constant even though energy is being added. Understanding this principle is crucial for many applications in physics, such as thermodynamics and material science.