If `Q` amount of heat is given to a diatomic ideal gas in a process in which the gas perform a work `(2Q)/(3)` on its surrounding. Find the molar heat capacity (in terms of `R`) for the process.

Answer

`7.5R`

Explanation

`Q = nCDeltaT`
As `Q = nC DeltaT` ………..(i)
Also `DeltaU = Q - (2Q)/(3) = (Q)/(3)`
`nC_(v)DeltaT = (Q)/(3), (n5RDeltaT)/(2) = (Q)/(3)`
`rArr nDeltaT = (2Q)/(15R) ………(ii)`
From (1) and (ii)
`C = (Q15R)/(2Q) = 7.5R`.