A model shows water vapor turning directly into solid ice without passing through the liquid phase. Which change of state is represented in this model?

• A. Freezing
• B. Boiling
• C. Deposition
• D. Condensation

Answer: (C)

Verified step by step guidance

1. Identify the process described: water vapor (gas phase) turning directly into solid ice (solid phase) without becoming liquid first.
2. Recall the common phase changes: freezing (liquid to solid), boiling (liquid to gas), condensation (gas to liquid), and deposition (gas to solid).
3. Understand that deposition is the phase change where a gas turns directly into a solid, bypassing the liquid phase.
4. Compare the given scenario to the definitions and recognize that the direct gas-to-solid transition matches deposition.
5. Conclude that the change of state represented in the model is deposition.