What term describes the amount of heat extracted when a substance changes from liquid to solid?

The correct answer is the latent heat of fusion, which describes the amount of heat extracted from a substance as it changes from a liquid to a solid. This process involves the transition of a material without a change in temperature, highlighting the energy required to overcome intermolecular forces during solidification.

In the case of water, for instance, when it freezes into ice, it releases heat energy—this is the latent heat of fusion. The term is crucial in refrigeration and phase change processes because it plays a significant role in how efficiently a refrigeration system can operate when removing heat from such transitions.

The other choices refer to different thermal processes. The latent heat of evaporation relates to the heat absorbed when a liquid turns into vapor, while specific heat capacity concerns the amount of heat needed to change the temperature of a substance without a phase change. Latent heat of sensation is not a standard term in thermodynamics, making it irrelevant in this context. Understanding these distinctions is vital for operators in refrigeration systems to manage the thermal dynamics effectively.