Answer: Cp - Cv = R.
- A Cp - Cv = R
- B Cp + Cv = R
- C Cp/Cv = R
- D Cp × Cv = R
Correct answer: A. Cp - Cv = R
Explanation: Mayers relation states that the difference between molar specific heats at constant pressure and constant volume equals the gas constant R.
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.