question_answer

The molar heat capacity of an ideal gas at constant pressure is greater than that at constant volume because :

A)  work has to be done against intermolecular forces as the gas expands

B)  work has to be done against thermal pressure as the gas expand            

C)  the molecules rotate more easily when the gas expands

D)  when the molecules are farther apart they collide less frequently and so do not get hot as easily