A certain ideal gas has a molar specific heat at constant pressure of 33.2 J/mol ∙ K.Its molar specific heat at constant volume is closest to which of the following values? (R = 8.31J/mol ∙ K)
A)41.9 J/mol ∙ K
B)16.6 J/mol ∙ K
C)25.1 J/mol ∙ K
D)24.9 J/mol ∙ K
E)49.8 J/mol ∙ K

Question

Quizplus · Accepted Answer

For an ideal gas, we have the relationship between the molar specific heats as follows:
Cp - Cv = R
where Cp and Cv are the molar specific heats at constant pressure and volume, respectively.
Substituting the given value of Cp and R, we get:
33.2 J/mol ∙ K - Cv = 8.31 J/mol ∙ K
Solving for Cv, we get:
Cv = 33.2 J/mol ∙ K - 8.31 J/mol ∙ K ≈ 24.9 J/mol ∙ K
Therefore, the closest value among the given choices is D.

A Certain Ideal Gas Has a Molar Specific Heat at Constant