$Zn\left( s \right) + C{u^{2 + }}\left( {aq} \right) \rightleftharpoons Z{n^{2 + }}\left( {aq} \right) + Cu\left( s \right)$
$300\,K$ એ પ્રમાણિત પ્રક્રિયા એન્થાલ્પી $\left( {{\Delta _r}{H^ - }} \right),\, kJ \,mol^{-1}$ માં કેટલા .............. $\mathrm{kJ}$ થશે?
$[R=8\,J\,K^{-1}\,mol^{-1}$ અને $F=96,000\,C\,mol^{-1}]$
\(\Delta S=nF\left( \frac{dE}{dT} \right)=2\times 96500\,\,\times (-5\times {{10}^{-4}}J{{/}^{o}}C)=-96.5\,kJ\)
at \(298\,K\)
\(T\Delta S=298\times \,(-96.5\,\,J)\,=\,-\,28.8\,kJ\)
at constant \(T\,(=\,248\,K)\) and pressure
\(\Delta G\, = \,\,\Delta H\, - \,\,T\Delta S{\mkern 1mu} \)
\(\Delta H\, = \,\,\Delta G\, + \,\,T\Delta S{\mkern 1mu} \)
\(=-386-28.8=-412.8\,kJ\)