Which term refers to the process of a solid changing to vapor without passing through a liquid state?

The term that refers to the process of a solid changing directly to vapor without transitioning through a liquid state is sublimation. This phenomenon occurs under specific conditions, primarily when a solid gains enough energy, often through heat, to convert directly into gas.

Sublimation is commonly observed with substances such as dry ice (solid carbon dioxide) or snow in freezing temperatures, where they seem to disappear without melting into a liquid. This process is different from evaporation, which specifically involves the transition of a liquid to a vapor.

Condensation is the opposite process, where vapor transforms back into a liquid, and vaporization refers to the general process of a substance transitioning from a liquid to gas, encompassing both evaporation and boiling. Therefore, sublimation is the correct term to describe the solid-to-vapor transition without the liquid phase.