Deposition is the direct transition of a substance from the gas phase to the solid phase, skipping the liquid state entirely. It is the reverse of sublimation.
How it works:
- When a gas loses enough thermal energy under certain conditions, its particles slow down and form a solid structure without first becoming a liquid.
- This typically happens at low temperatures and/or high pressures, where the gas can condense directly into a solid.
Examples of deposition:
- Frost formation on cold surfaces when water vapor turns directly into ice.
- Soot formation in chimneys where gas-phase carbon condenses into solid particles.
- Thin-film deposition in manufacturing (e.g., making semiconductors or coatings using vapor deposition techniques).
Deposition is important in meteorology, material science, and space science, offering insights into how solids can form from gases under extreme or controlled conditions.