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Given below are observations on molar sp...

Given below are observations on molar specific heats at room temperature of some common gases.

The measured molar specific heats of these gases are markedly different from those for monatomic gases. Typically, molar specific heat of a monatomic gas is 2.92 cal/mol K. Explain this difference. What can you infer from the somewhat larger (than the rest) value for chlorine ?

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Gases given in the question are diatomic. Their specific heat is `5/2R=5/2xx1.98=4.95`.
All the gases except chlorine gas have same specific heat as above.
Diaformic gases atoms perform vibrational and rotation motion with translational motion. And nonatomic gas atoms only perform translational motion. Hence specific heat of monoatomic gas is less than specific heat of diatomic gas.
The higher value of molar specific heat of chlorine indicats that besides rotational modes, vibrational modes are also present in chlorine at room temperature.
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Given below are observations on molar specific heats at room temperature of some common gases. {:("Gas","Molar specific heat "(C_(v))),(,("cal mol"^(1)K^(-1))),("Hydrogen",4.87),("Nitrogen",4.97),("Oxygen",5.02),("Nitric oxide",4.99),("Carbon monoxide",5.01),("Chlorine",6.17):} The measured molar specific heats of these gases are markedly different from those for monatomic gases. Typically, molar specific heat of a monatomie gas is 2.52 cal/mol K. Explain this difference. What can you infer from the somewhat larger than the rest) value for chlorine ?

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