Answer: decreases by about 0.54%.
- A increases by about 0.54%
- B decreases by about 1.8%
- C decreases by about 0.54%
- D essentially unchanged
Correct answer: C. decreases by about 0.54%
Explanation: Δρ/ρ ≈ -γΔT = -5.4×10<sup>-5</sup> × 100 = -0.0054, a 0.54% decrease.
During a phase change (melting or boiling), temperature stays constant while heat is absorbed entirely as latent heat (Q=mL); temperature only rises again once the substance is fully in its new phase.
Concept context
Temperature scales, thermal expansion, calorimetry, and the three modes of heat transfer including radiation laws.