What is the process of converting a solid directly into a gas called?

Sublimation is the process through which a solid transitions directly into a gas without passing through the liquid state. This phenomenon occurs under specific conditions of temperature and pressure, allowing certain substances, such as dry ice (solid carbon dioxide) and iodine, to vaporize directly from solid form into gas. It is a physical change that allows for a unique transformation and is essential for various applications, including freeze-drying and certain industrial processes. Understanding sublimation can also deepen knowledge about phase changes in materials and their behavior under varying environmental conditions.