Molar Heat Capacities – Rankers Physics

Thermodynamics: Practice Problem & Solution

Assertion (A): Molar heat capacity at constant pressure can be less than molar heat capacity at constant volume. Reason (R): \( C_p - C_V = R \) is valid only for ideal monoatomic gas.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Thermodynamics. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is false; \( C_p \) is always greater than \( C_V \) because work is done at constant pressure.

Reason (R) is false; Mayer's relation, \( C_p - C_V = R \), is valid for all ideal gases, regardless of atomicity.

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