Starting from the relation $dH=(\partial H/\partial T)_P dT+(\partial H/\partial P)_T dP$, we obtain: \begin{equation} \Delta H=\int_{1}^{ 2}C_pdT + \int_{1}^{2}(V-TV\alpha)dP \end{equation} $\Delta U$ can be obtained by the expression: $\Delta U=\Delta H -\Delta(PV )$