NCERT Exercise 10.15 - Thermal Properties of Matter
Question: Measured molar Cv of diatomic gases (H2, N2, O2, etc.) are about 5 cal/(mol K), while monatomic gases have about 2.92 cal/(mol K). Explain the difference. Why is Cl2 somewhat higher?
Answer: Diatomic Cv = **(5/2)R due to rotational degrees of freedom**; Cl2 higher due to **partial vibrational contribution**.
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