${Zn}\left|{Zn}^{2+}({aq}),(1 {M}) \| {Fe}^{3+}({aq}), {Fe}^{2+}({aq})\right| {Pt}({s})$
કોષ પોટેન્શિયલ $1.500\, {~V}$ પર ${Fe}^{3+}$ આયન તરીકે હાજર કુલ આયનનો અપૂર્ણાંક, ${X} \times 10^{-2}$ છે. $X$ નું મૂલ્ય $.....$ (નજીકના પૂર્ણાંકમાં) છે.
$\left(\right.$ આપેલ છે: $\left.E_{{Fe}^{3+} / {Fe}^{2+}}^{0}=0.77\, {~V}, {E}_{{Zn}^{2+} / {Zn}}^{0}=-0.76 \,{~V}\right)$
\(2 {Fe}^{3+} \longrightarrow {e}^{-}+{e}^{2+}\)
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\({Zn}+2 {Fe}^{3+} \longrightarrow {Zn}^{2+}+2 {Fe}^{2+}\)
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\({E}_{{cell}}^{0}=0.77-(0.76)\)
\(=1.53 {~V}\)
\(1.50=1.53-\frac{0.06}{2} \log \left(\frac{{Fe}^{2+}}{{Fe}^{3+}}\right)^{2}\)
\(\log \left(\frac{{Fe}^{2+}}{{Fe}^{3+}}\right)=\frac{0.03}{0.06}=\frac{1}{2}\)
\(\frac{\left[{Fe}^{2+}\right]}{\left[{Fe}^{3+}\right]}=10^{1 / 2}=\sqrt{10}\)
\(\frac{\left[{Fe}^{3+}\right]}{\left[{Fe}^{2+}\right]}=\frac{1}{\sqrt{10}}frac{\left[{Fe}^{3+}\right]}{\left[{Fe}^{2+}\right]+\left[{Fe}^{3+}\right]}\)
\(\frac{1}{1+\sqrt{10}}=\frac{1}{4.16}\)
\(=0.2402\)
\(=24 \times 10^{-2}\)
$P (5.0 × 10^{-5}), Q (7.0 × 10^{-8}), R (1.0 × 10^{-10}), S (9.2 × 10^{-3})$
$E.C.E\, Zn=32.5\,, \,E.C.E \,Cu=31.5)$
$Fe_{(aq)}^{3 + } + {e^ - } \to Fe_{(aq)}^{2 + }$ ; ${E^o} = 0.771{\mkern 1mu} \,volts;{\mkern 1mu} $
${\mkern 1mu} {I_{2(g)}} + 2{e^ - } \to 2I_{(aq)}^ - \,;{\mkern 1mu} $ ${E^o} = 0.536{\mkern 1mu} \,volts$
કોષ પક્રિયા $2Fe^{3+}_{(aq)} + 2l^{-}_{(aq)} \rightarrow 2Fe^{2+}_{(aq)} + I_{2(g)}$ માટે $E^o_{cell} = ….$