For reversible Galvanic cell, thermodynamic parameters are given as : 

$$\begin{gathered} {\left(\Delta G\right)}_{T.P}=\Delta H-T\Delta S, \\ {\left(\Delta G\right)}_{T.P}=-nF{E}_{cell,} \\ \Delta S=nF{\left[\frac{d{E}_{cell}}{dT}\right]}_P, \\ {W}_{usefull}=-{\left(\Delta G\right)}_{T.P} \end{gathered}$$

$forgivencellPt\left|H_2\right|HCl\left|AgCl\right|, Ag,$ variation of e.m.f. of the cell with temperature is given as $E_{cell}\left(involt\right)=0.4-[2\times {10}^{-6}{\left(T\right)}^2]$ (T = temperature in Kelvin). (Use : 1F = 96500 C)