$Pt ( s )\left| H _2( s )( latm )\right| H ^{+}\left( aq ,\left[ H ^{+}\right]=1\right)|| Fe ^{3+}( aq ), Fe ^{2+}( aq ) \mid \operatorname{Pt}( s )$
આપેલ : $E _{ Fe ^{3+} / e ^{2 *}}^0=0.771\,V$ અને $E _{ H ^{+}+\frac{1}{2} H _2}^0=0\,V , T =298\,K$
જો કોષનો પોટેન્શિયલ $0.712\,V$, હોય, તો $Fe ^{-2}$ થી $Fe ^{+3}$ ની સાંદ્રતાની ગુણોત્તર છે.(નજીકનો પૂર્ણાંક)
$E = E ^{\circ}-\frac{0.059}{1} \log \frac{\left[ Fe ^{2+}\right]}{\left\lfloor Fe ^{3+}\right\rfloor}$
$\Rightarrow \quad 0.712=(0.771-0)-\frac{0.059}{1} \log \frac{\left[ Fe ^{2+}\right]}{\left[ Fe ^{3+}\right]}$
$\Rightarrow \quad \log \frac{\left[ Fe ^{2+}\right]}{\left[ Fe ^{3+}\right]}=\frac{(0.771-0712)}{0.059}=1$
$\Rightarrow \frac{\left[ Fe ^{2+}\right]}{\left[ Fe ^{3+}\right]}=10$
$Cu(s) + 2Ag{^+}_{(aq)} \to Cu^{+2}_{(aq)} + 2Ag(s)$
માટે સંતુલન અચળાંક $K_C = 10 \times 10^{15}$ છે, તો $298\, K$ ને $E_{cell}^o$ નું મૂલ્ય કેટલુ થશે?
[${2.303\,\frac{{RT}}{F}}$ એ $298\,K$ $=0.059\,V$]
$Z{n^{2 + }}\,(aq)\, + \,2e\, \rightleftharpoons \,Zn\,(s)\,;\, - \,0.762\,V$
$C{r^{3 + }}\,(aq)\, + \,3e\, \rightleftharpoons \,Cr(s)\,;\, - \,0.740\,\,V$
$2{H^ + }\,(aq)\, + \,2e\, \rightleftharpoons \,{H_2}(g)\,;\,\,\,0.00\,\,\,V$
$F{e^{3 + }}\,(aq)\, + \,e\, \rightleftharpoons \,F{e^{2 + }}(aq)\,;\,\,\,0.770\,\,\,V$
નીચેનામાંથી કયો પ્રબળ રીડક્ષન કર્તા છે ?
$E^o_{Cr_2/O_7^{2-}/Cr^{3+}}=1.33\,V,$ $E^o_{MnO^-_4/Mn^{2+}} = 1.51\,V$
તો નીચેના પૈકી સૌથી પ્રબળ રિડક્શતકર્તા ..........
(નજીકના પૂર્ણાંકમાં રાઉન્ડ ઑફ કરો) $[$ આપેલ $\left.: \frac{2.303 RT }{ F }=0.059\right]$
$Zn^{2+}(aq) + 2e^{-} $ $\rightleftharpoons$ $ Zn (s)$ , $E^o_{RP}= -0.762\, V$,
$Cr^{3+}(aq) + 3e^{-} $ $\rightleftharpoons$$ Cr(s)$, $E^o_{RP} = -0.740\, V$
$2H^{+}(aq) + 2e^{-} $$\rightleftharpoons$$ H_2(g)$, $E^o_{RP} = 0.00\,V$,
$Fe^{3+}_{(aq)} + 2e^{-} $$\rightleftharpoons$$ Fe^{2+}(aq)$ , $E^o_{RP} = 0.77 \,V$