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At N.T.P., 1 mole of a gas has a volume of 22.4 L. Determine the difference between its two molar specific heats. Take J = 4200 J/kcal.

1. 1.979 kcal/kmol K
2. 2.378 kcal/kmol K
3. 4.569 kcal/kmol K
4. 3.028 kcal/kmol K

Correct answer: 1.979 kcal/kmol K

Solution

The difference between the molar specific heats of a gas can be calculated using the ideal gas law and the relationship between heat capacities. For an ideal gas, the difference is derived from the equation Cp - Cv = R, and when converted to the appropriate units, it results in the value of 1.979 kcal/kmol K.

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