What is the term for the process in which a solid transitions directly to a vapor?

Sublimation is the term that describes the process where a solid transitions directly to a vapor without going through the liquid phase. This phenomenon occurs when the molecules in a solid gain enough energy to overcome intermolecular forces and escape into the gas phase. A common example of sublimation is dry ice (solid carbon dioxide), which turns directly into carbon dioxide gas at atmospheric pressure. Understanding sublimation is crucial in various applications, including freeze-drying in food preservation and the behavior of certain materials in different environmental conditions.

The other terms represent different phase changes: condensation refers to the transformation from vapor to liquid, vaporization is the general process of a liquid transitioning to a vapor (which includes both boiling and evaporation), and evaporation specifically refers to the transition of a liquid to vapor at temperatures below boiling point. These processes do not involve moving from a solid directly to a vapor, thus highlighting why sublimation is the correct answer.