Molar specific heat at constant volume of a diatomic gas with one vibrational mode (non-rigid)

The same question, asked 2 times: 4 May 2023 S1, 13 Apr 2026 S2. Every wording below, oldest first.

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Question 1
4 May 2023 S1
1 $According to the law of equipartition of energy, the molar specific heat of a diatomic gas at constant volume where the molecule has one additional vibrational mode is$
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Question 2
13 Apr 2026 S2
117 $According to law of equipartition of energy the molar specific heat of a non rigid diatomic gas at constant volume is$
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