How is latent heat defined?

Latent heat is defined as the heat that causes a change of state without changing the temperature of a substance. This definition is fundamental in thermodynamics and is crucial when considering processes such as melting, freezing, boiling, or condensing.

When a substance undergoes a phase change, such as ice melting into water or water vapor condensing back into liquid water, it requires energy to be absorbed or released. This energy is known as latent heat. For instance, when ice melts at 0 degrees Celsius, it absorbs heat from the surroundings; however, the temperature of the ice-water mixture remains constant during this process. Similarly, when water boils at 100 degrees Celsius, heat is absorbed to convert the liquid into steam without increasing the temperature of the water.

Understanding latent heat is critical for engineers and scientists as it plays a significant role in climate studies, refrigeration, heating systems, and various engineering applications where phase changes occur.