What term describes the transition of a substance from the solid phase to the liquid phase?

The transition of a substance from the solid phase to the liquid phase is known as melting. This process occurs when a solid is heated, causing its particles to gain energy and move apart, which allows the substance to change to a liquid state. Melting is a significant physical change, and it can be observed in various materials, such as ice transforming into water.

The other options refer to different processes: condensation involves the transition from gas to liquid, freezing is the process of a liquid turning into a solid, and sublimation describes the transition from solid directly to gas without passing through the liquid phase. Understanding these distinctions is crucial in the study of phase changes in matter.