What type of heat change occurs when heat flow doesn't result in a temperature change?

Latent heat is the type of heat change that occurs when heat flow does not result in a temperature change. This phenomenon happens during phase changes of a substance, such as when ice melts to water or when water boils into steam. During these transitions, the heat energy added to the system is used to overcome the forces holding the molecules together in their solid or liquid states, rather than increasing the temperature of the substance.

In the case of melting ice, even though heat is being added to the ice, the temperature remains at 0 degrees Celsius until all the ice has transformed into water. Similarly, when water is boiling, it remains at 100 degrees Celsius at standard atmospheric pressure until all the liquid has converted to vapor. This illustrates the unique nature of latent heat, distinguishing it from other forms of heat transfer which directly lead to temperature changes in a substance.