The process that allows a solid to convert directly to a gas is known as sublimation. In sublimation, a substance transitions from its solid phase to the gaseous phase without passing through the liquid phase. This phenomenon occurs under specific conditions, typically involving low pressure and/or high temperature. Common examples of sublimation include dry ice (solid carbon dioxide) and iodine, which both release gas directly from the solid state. Sublimation has applications in various scientific and industrial processes, such as freeze-drying.