Which phase transition does latent heat primarily involve?

• A. Solid to liquid transition
• B. Liquid to vapour transition
• C. Vapour to liquid transition
• D. Sublimation

Answer: (C)

Latent heat is the energy absorbed or released by a substance during a phase transition, without a change in temperature. When discussing latent heat, it is essential to consider the processes where this energy transfer occurs.

The transition from vapour to liquid is known as condensation. During this phase transition, water vapour releases energy in the form of latent heat, which is a key concept in thermodynamics and meteorology. This release of energy happens as the vapour molecules lose kinetic energy and come together to form liquid, making this process an important part of the water cycle and various industrial applications.

Understanding latent heat in the context of phase transitions highlights its physical significance. In contrast, the other transitions listed—solid to liquid, liquid to vapour, and sublimation—are associated with different heat exchanges: fusion, vaporization, and sublimation respectively. While these processes also involve latent heat, the specific focus on vapour to liquid transition emphasizes the heat released and the implications of condensation in energy and environmental systems.