Let initial pressure, volume, temperature be P0,V0,T0 indicated by state A in P-V diagram. The gas isthen inochorically taken to state B (2P0,V0,2T0 ) and then taken from state B to state C (2P0,2V0,4T0) isobarically
Total heat absorbed by 1 mole of gas ΔQ = Cv (2T0−T0) + Cp (4T0−2T0) =
5
2
RT0 +
7
2
R×2T0 =
19
2
RT0 Total change in temperature from state A to C is ΔT = 3T0 ∴ Molar heat capacity =