Chapter 5 – Practice Problem (Phase Transitions – Melting, Boiling, and Subliming) Solutions – Odd Answers

1. Melting is the phase change from a solid to a liquid, whereas solidification is the phase change from a liquid to a solid.

3. The molecules have enough energy to move about each other but not enough to completely separate from each other.

5. 890 J

7. 10.7 kJ

9.

• a. Temperature does not change during a phase change.
• b. The process of a liquid becoming a gas is called boiling; the process of a solid becoming a gas is called sublimation.

11. Na(s) → Na(ℓ)

13. CO₂(s) → CO₂(g)

15. 46.69 kJ/mol