An ideal gas consisting of `N-`atomic molecules is expanded isobarically. Assuming that all degrees of freedom (translational, rotational, and vibrational) of the molecules are excited, find what fraction of heat transferred to the gas in this process is spend to perform the work of expansion. Now high is this fraction in the case of monatomic gas ?

Explanation

In the isobaric process, work done is
`A = pdv = RdT` per mole.
One the other hand heat transferred `Q = C_p dT`
Now `C_p = (3N - 2)R` for non-collinear molecules and `C_p = (3 N - (3)/(2)) R` for linear molecules
Thus `(A)/(Q) ={((1)/(3 N-1),non colli n ear,,),((1)/(3 N - 3/2 ),li n ear,,):}`
For monoatomic gases, `c_p = (5)/(2)` and `(A)/(Q) = (2)/(5)`.