Practice Question
A substance is placed in a laboratory freezer at very low temperature. After several hours, the solid sample becomes smaller, but no liquid is ever observed. Instead, gas particles are detected in the air inside the freezer.
Which process best explains this change?
A. Melting
B. Condensation
C. Sublimation
D. Deposition
Question
A scientist notices that frost forms on the inside of a freezer when water vapor in the air turns directly into ice without becoming liquid water first.
What process is occurring?
A. Freezing
B. Condensation
C. Sublimation
D. Deposition
#Sublimation is the process when a solid changes directly into a gas without becoming a liquid first.
Simple example:
• Dry ice (#solid #carbon #dioxide) → #gas
• Snow or ice slowly disappearing on a cold day without melting
This is different from:
• Melting: solid → liquid
• Boiling/Evaporation: liquid → gas
• Condensation: gas → liquid
- Melting: solid → liquid
- Freezing: liquid → solid
- Boiling / Evaporation: liquid → gas
- Condensation: gas → liquid
- Sublimation: solid → gas (skips liquid)
- Deposition: gas → solid