Deposition is the process in which a gas changes directly into a solid without first becoming a liquid.
Key points:
- It is the reverse of sublimation.
- Occurs when gas molecules lose energy rapidly and stick together to form a solid.
- Happens under low temperature or high pressure conditions.
Examples of Deposition:
- Frost forming on cold surfaces in winter (water vapor → ice).
- Iodine vapor turning into solid iodine crystals.
- Snow formation in clouds (water vapor → snow).
Importance:
- Plays a role in weather phenomena like frost and snow.
- Used in purification of substances by deposition.