$Zn\,(s)\,\, + \,\,C{u^{2 + }}\,(aq)\, \rightleftharpoons \,Z{n^{2 + \,}}\,(aq)\, + Cu\,(s)$
$(R = 8 \,JK^{-1}\,mol^{-1},\, F = 96000\,C\,mol^{-1})$
\( - nF{E_{cell}}\, = \, - \,RT\ln \,K\)
\(\ln \,K\, = \,\frac{{2\, \times \,96500\, \times \,2}}{{8\, \times \,300}}\, = \,160.83\)
\(K\, = \,{e^{160}}\)
$298\,K$ પર જ્યારે $\frac{\left[M^*(a q)\right]}{\left[M^{3 *}(a q)\right]}=10^a$ હોય ત્યારે આપેલ કોષ નો $E_{\text {cell }}$ એ $0.1115\,V$ છે. $a$ નું મૂલ્ય $............$ છે.આપેલ : $E _{ M }^\theta{ }^{3+} M ^{+}=0.2\,V$
$\frac{2.303\,R T}{F}=0.059\,V$
$Zn | Zn ^{2+}(0.1\, M ) \| Ag ^{+}(0.01 \,M )| Ag$
[આપેલ $: E_{Z n^{+2}/Z_{n}}^{0}=-0.76 \,V ; E _{A g^{+} / A_{ g }}^{0}=+0.80 \,V ; \frac{2.303 RT }{ F }=0.059$]