The molar heat capacity for a gas at constant T and P is :
Correct answer: D. Infinity
- A. 3/2R
- B. 5/2R
- C. Dependent on the atomicity of the gas
- D. Infinity
Explanation
When a gas is at constant temperature and pressure, adding heat does not change the temperature, which means the heat capacity is theoretically infinite. This is because the added heat is used to perform work or cause a phase change rather than increase temperature. Therefore, there is no limit to how much heat can be added without changing the temperature. The other options represent molar heat capacities at constant volume for specific types of gases or depend on atomic structure, which are not relevant under constant temperature and pressure conditions.
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About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
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