What is the process by which a solid turns directly into a gas?

The process where a solid turns directly into a gas is known as sublimation. This phenomenon occurs without the solid passing through a liquid state. A well-known example of sublimation is dry ice (solid carbon dioxide), which changes directly to carbon dioxide gas at room temperature under normal atmospheric pressure.

This transformation suggests that under certain conditions, such as specific temperature and pressure scenarios, solids can convert to gas due to an increase in energy, allowing the molecules to escape the solid structure without transitioning to the liquid phase. Understanding sublimation is crucial in various applications, including freeze-drying and the production of certain types of gases from solids in chemical processes.