The process of converting a solid directly to a gas is called sublimation. This transformation occurs without passing through the liquid state. Sublimation is commonly seen in substances like dry ice (solid carbon dioxide) and snow, which can directly evaporate into water vapor under certain conditions. The process requires an increase in energy, typically through heat, causing molecules in the solid to gain enough energy to escape into the gaseous phase. Sublimation has various applications, including freeze-drying in food preservation and the production of specific chemicals in laboratories.