What phase is characterized by the transition of a solid into vapor without passing through the liquid phase?

Sublimation is a process where a solid transitions directly into vapor without first becoming liquid. This occurs under specific conditions, typically involving low pressure and/or high temperatures that favor the gaseous state. A common example of sublimation is the way dry ice (solid carbon dioxide) changes into carbon dioxide gas at room temperature.

In contrast, evaporation refers to the transition of a liquid into vapor, while condensation is the process by which vapor turns back into a liquid. Precipitation involves the formation of solid or liquid water from atmospheric moisture, often resulting from cooling or saturation in the atmosphere, and does not pertain to the direct conversion of solids to gases. This makes sublimation a distinct phase change focused solely on the solid-to-vapor transition.