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

Short Solution (Best for NEET):

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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