What do we call heat that is added to a vapor after a change of state has occurred?

The term for heat that is added to a vapor after a change of state has occurred is known as "superheat." When a substance undergoes a phase change, such as from liquid to vapor, it absorbs heat without a change in temperature during the phase transition; this is referred to as latent heat. However, once the substance has completely vaporized and additional heat is added, the temperature of the vapor increases. This added heat, which results in a rise in temperature of the vapor beyond its boiling point, is classified as superheat.

Superheating is an important concept in various applications, such as in refrigeration and air conditioning systems, where it is essential to ensure that the refrigerant exiting the evaporator coil is in the superheated state to prevent liquid from returning to the compressor, which can cause damage and inefficiency.