Heat added to a vapor after the change of state is called?

• A. Latent heat
• B. Sensible heat
• C. Subcooling
• D. Superheat

Answer: (D)

When a liquid has boiled and become vapor, any additional heat goes into raising the temperature of that vapor above its saturation temperature. This extra energy is called superheat. It distinguishes the state after the phase change from the energy used to cause the phase change itself (latent heat), which occurs at constant temperature. Sensible heat, in contrast, is the heat that changes temperature within a single phase (solid, liquid, or gas) without changing phase. Subcooling refers to cooling a liquid below its boiling point when it is not yet vaporized. So, because the heat is added to a vapor after it has changed state, the correct term is superheat.