In a cell, the following reactions take place
$$\matrix{ {F{e^{2 + }} \to F{e^{3 + }} + {e^ - }} & {E_{F{e^{3 + }}/F{e^{2 + }}}^o = 0.77\,V} \cr {2{I^ - } \to {I_2} + 2{e^ - }} & {E_{{I_2}/{I^ - }}^o = 0.54\,V} \cr } $$
The standard electrode potential for the spontaneous reaction in the cell is x $\times$ 10$-$2 V 298 K. The value of x is ____________. (Nearest Integer)
Answer (integer)
23
Solution
$\underset{\text { Cathode }}{\mathrm{Fe}^{+3}}+\underset{\text { anode }}{\mathrm{I}^{-}} \longrightarrow \mathrm{I}_2+\mathrm{Fe}^{+2}$<br/><br/>
$E_{\text {cell }}^{\circ}=E_{\text {cathode }}^{\circ}-E_{\text {anode }}^{\circ}$
<br/><br/>
$$
\begin{aligned}
&=0.77-0.54 \\\\
&=0.23 \mathrm{~V} \\\\
&=23 \times 10^{-2} \mathrm{~V}
\end{aligned}
$$
About this question
Subject: Chemistry · Chapter: Electrochemistry · Topic: Electrochemical Cells
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