Electrochemical Cells or Galvanic Cells
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CHXII03:ELECTROCHEMISTRY

330066 The oxidation potentials of \({\rm{Zn,}}\,\,{\rm{Cu,}}\,\,{\rm{Ag,}}\,\,{{\rm{H}}_{\rm{2}}}\,\,{\rm{and}}\,\,{\rm{Ni}}\) are \({\rm{0}}{\rm{.76, - 0}}{\rm{.34, - 0}}{\rm{.80, 0}}{\rm{.00, 0}}{\rm{.25}}\) volt, respectively. Which of the following reactions will provide maximum voltage?

1 \({{\text{H}}_{\text{2}}}{\text{ + N}}{{\text{i}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Ni}}\)
2 \({{\text{H}}_{\text{2}}}{\text{ + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Cu}}\)
3 \({\text{Zn + 2A}}{{\text{g}}^{\text{ + }}} \to {\text{2Ag + Z}}{{\text{n}}^{{\text{2 + }}}}\)
4 \({\text{Zn + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{Cu + Z}}{{\text{n}}^{{\text{2 + }}}}\)
CHXII03:ELECTROCHEMISTRY

330067 If the half-cell reactions are given as
\({\rm{ I}}{\rm{. F}}{{\rm{e}}^{2 + }}({\rm{aq}}) + 2{{\rm{e}}^ - } \to {\rm{Fe(s)}},{\rm{E}}^\circ = - 0.44\;{\rm{V}}\)
\({\rm{II}}{\rm{. }}2{{\rm{H}}^ + }{\rm{(aq)}} + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} + 2{{\rm{e}}^ - } \to {{\rm{H}}_2}{\rm{O}}(l),\)
\(\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{E}}^\circ = + 1.23\;{\rm{V}}\)
then \({\rm{E}}^\circ \) for the reaction,
\({\rm{Fe(s)}} + 2{{\rm{H}}^ + } + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} \to {\rm{F}}{{\rm{e}}^{2 + }}{\rm{(aq)}} + {{\rm{H}}_2}{\rm{O}}({\rm{l}})\)

1 \(+1.67 \mathrm{~V}\)
2 \(-1.67 \mathrm{~V}\)
3 \(+0.79 \mathrm{~V}\)
4 \(-0.79 \mathrm{~V}\)
CHXII03:ELECTROCHEMISTRY

330068 The EMF of the cell \(\left. {{\text{Ni}}} \right \vert \left. {{\text{N}}{{\text{i}}^{{\text{2 + }}}}} \right\vert \left. {{\text{C}}{{\text{u}}^{{\text{2 + }}}}} \right \vert {\text{Cu}}\left( {\text{s}} \right)\) is 0.59 volt. The standard reduction electrode potential of copper electrode is 0.34 volt. The standard reduction electrode potential of nickel electrode will be

1 –0.025 volt
2 –0.50 volt
3 0.25 volt
4 –0.25 volt
CHXII03:ELECTROCHEMISTRY

330069 The \({{\rm{E}}^{\rm{o}}}\) for the following cell is 0.34 V. \(\left. {{\rm{In(s)}}} \right \vert \left. {{\rm{In(OH}}{{\rm{)}}_{\rm{3}}}{\rm{(aq)}}} \right\vert \left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}{\rm{(aq)}}} \right \vert {\rm{Sb(s)}}\)
[Using \({{\rm{E}}^{\rm{o}}}{\rm{ = - 1}}{\rm{.0V}}\) for the \(\left. {{\rm{In(O}}{{\rm{H}}_{\rm{3}}}{\rm{)}}} \right \vert \) In couple, calculate \({{\rm{E}}^{\rm{o}}}\) for the \(\left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}} \right \vert {\rm{Sb}}\) half-reaction:]

1 \({\rm{ - 1}}{\rm{.34}}\)
2 \({\rm{ + 0}}{\rm{.66}}\)
3 \( + 0.82\)
4 \( - 0.66\)
CHXII03:ELECTROCHEMISTRY

330070 The standard electrode potential for the half cell reactions are
\({\rm{Z}}{{\rm{n}}^{{\rm{2 + }}}} + 2{e^ - } \to Zn;\,\,{E^o} = - 0.76\,\,V\)
\(F{e^{2 + }} + 2{e^ - } \to Fe;\,\,{E^o} = - 0.44\,\,V\)
The e.m.f of the cell reaction
\(F{e^{2 + }} + Zn \to Z{n^{2 + }} + Fe\)

1 \({\rm{ - 1}}{\rm{.20}}\,\,{\rm{V}}\)
2 \({\rm{ + 1}}{\rm{.20}}\,\,{\rm{V}}\)
3 \({\rm{ + 0}}{\rm{.32}}\,\,{\rm{V}}\)
4 \({\rm{ - 0}}{\rm{.32}}\,\,{\rm{V}}\)
KCET - 2009
NEET DIGITAL LIBRARY
CHXII03:ELECTROCHEMISTRY

330066 The oxidation potentials of \({\rm{Zn,}}\,\,{\rm{Cu,}}\,\,{\rm{Ag,}}\,\,{{\rm{H}}_{\rm{2}}}\,\,{\rm{and}}\,\,{\rm{Ni}}\) are \({\rm{0}}{\rm{.76, - 0}}{\rm{.34, - 0}}{\rm{.80, 0}}{\rm{.00, 0}}{\rm{.25}}\) volt, respectively. Which of the following reactions will provide maximum voltage?

1 \({{\text{H}}_{\text{2}}}{\text{ + N}}{{\text{i}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Ni}}\)
2 \({{\text{H}}_{\text{2}}}{\text{ + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Cu}}\)
3 \({\text{Zn + 2A}}{{\text{g}}^{\text{ + }}} \to {\text{2Ag + Z}}{{\text{n}}^{{\text{2 + }}}}\)
4 \({\text{Zn + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{Cu + Z}}{{\text{n}}^{{\text{2 + }}}}\)
CHXII03:ELECTROCHEMISTRY

330067 If the half-cell reactions are given as
\({\rm{ I}}{\rm{. F}}{{\rm{e}}^{2 + }}({\rm{aq}}) + 2{{\rm{e}}^ - } \to {\rm{Fe(s)}},{\rm{E}}^\circ = - 0.44\;{\rm{V}}\)
\({\rm{II}}{\rm{. }}2{{\rm{H}}^ + }{\rm{(aq)}} + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} + 2{{\rm{e}}^ - } \to {{\rm{H}}_2}{\rm{O}}(l),\)
\(\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{E}}^\circ = + 1.23\;{\rm{V}}\)
then \({\rm{E}}^\circ \) for the reaction,
\({\rm{Fe(s)}} + 2{{\rm{H}}^ + } + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} \to {\rm{F}}{{\rm{e}}^{2 + }}{\rm{(aq)}} + {{\rm{H}}_2}{\rm{O}}({\rm{l}})\)

1 \(+1.67 \mathrm{~V}\)
2 \(-1.67 \mathrm{~V}\)
3 \(+0.79 \mathrm{~V}\)
4 \(-0.79 \mathrm{~V}\)
CHXII03:ELECTROCHEMISTRY

330068 The EMF of the cell \(\left. {{\text{Ni}}} \right \vert \left. {{\text{N}}{{\text{i}}^{{\text{2 + }}}}} \right\vert \left. {{\text{C}}{{\text{u}}^{{\text{2 + }}}}} \right \vert {\text{Cu}}\left( {\text{s}} \right)\) is 0.59 volt. The standard reduction electrode potential of copper electrode is 0.34 volt. The standard reduction electrode potential of nickel electrode will be

1 –0.025 volt
2 –0.50 volt
3 0.25 volt
4 –0.25 volt
CHXII03:ELECTROCHEMISTRY

330069 The \({{\rm{E}}^{\rm{o}}}\) for the following cell is 0.34 V. \(\left. {{\rm{In(s)}}} \right \vert \left. {{\rm{In(OH}}{{\rm{)}}_{\rm{3}}}{\rm{(aq)}}} \right\vert \left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}{\rm{(aq)}}} \right \vert {\rm{Sb(s)}}\)
[Using \({{\rm{E}}^{\rm{o}}}{\rm{ = - 1}}{\rm{.0V}}\) for the \(\left. {{\rm{In(O}}{{\rm{H}}_{\rm{3}}}{\rm{)}}} \right \vert \) In couple, calculate \({{\rm{E}}^{\rm{o}}}\) for the \(\left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}} \right \vert {\rm{Sb}}\) half-reaction:]

1 \({\rm{ - 1}}{\rm{.34}}\)
2 \({\rm{ + 0}}{\rm{.66}}\)
3 \( + 0.82\)
4 \( - 0.66\)
CHXII03:ELECTROCHEMISTRY

330070 The standard electrode potential for the half cell reactions are
\({\rm{Z}}{{\rm{n}}^{{\rm{2 + }}}} + 2{e^ - } \to Zn;\,\,{E^o} = - 0.76\,\,V\)
\(F{e^{2 + }} + 2{e^ - } \to Fe;\,\,{E^o} = - 0.44\,\,V\)
The e.m.f of the cell reaction
\(F{e^{2 + }} + Zn \to Z{n^{2 + }} + Fe\)

1 \({\rm{ - 1}}{\rm{.20}}\,\,{\rm{V}}\)
2 \({\rm{ + 1}}{\rm{.20}}\,\,{\rm{V}}\)
3 \({\rm{ + 0}}{\rm{.32}}\,\,{\rm{V}}\)
4 \({\rm{ - 0}}{\rm{.32}}\,\,{\rm{V}}\)
KCET - 2009
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CHXII03:ELECTROCHEMISTRY

330066 The oxidation potentials of \({\rm{Zn,}}\,\,{\rm{Cu,}}\,\,{\rm{Ag,}}\,\,{{\rm{H}}_{\rm{2}}}\,\,{\rm{and}}\,\,{\rm{Ni}}\) are \({\rm{0}}{\rm{.76, - 0}}{\rm{.34, - 0}}{\rm{.80, 0}}{\rm{.00, 0}}{\rm{.25}}\) volt, respectively. Which of the following reactions will provide maximum voltage?

1 \({{\text{H}}_{\text{2}}}{\text{ + N}}{{\text{i}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Ni}}\)
2 \({{\text{H}}_{\text{2}}}{\text{ + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Cu}}\)
3 \({\text{Zn + 2A}}{{\text{g}}^{\text{ + }}} \to {\text{2Ag + Z}}{{\text{n}}^{{\text{2 + }}}}\)
4 \({\text{Zn + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{Cu + Z}}{{\text{n}}^{{\text{2 + }}}}\)
CHXII03:ELECTROCHEMISTRY

330067 If the half-cell reactions are given as
\({\rm{ I}}{\rm{. F}}{{\rm{e}}^{2 + }}({\rm{aq}}) + 2{{\rm{e}}^ - } \to {\rm{Fe(s)}},{\rm{E}}^\circ = - 0.44\;{\rm{V}}\)
\({\rm{II}}{\rm{. }}2{{\rm{H}}^ + }{\rm{(aq)}} + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} + 2{{\rm{e}}^ - } \to {{\rm{H}}_2}{\rm{O}}(l),\)
\(\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{E}}^\circ = + 1.23\;{\rm{V}}\)
then \({\rm{E}}^\circ \) for the reaction,
\({\rm{Fe(s)}} + 2{{\rm{H}}^ + } + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} \to {\rm{F}}{{\rm{e}}^{2 + }}{\rm{(aq)}} + {{\rm{H}}_2}{\rm{O}}({\rm{l}})\)

1 \(+1.67 \mathrm{~V}\)
2 \(-1.67 \mathrm{~V}\)
3 \(+0.79 \mathrm{~V}\)
4 \(-0.79 \mathrm{~V}\)
CHXII03:ELECTROCHEMISTRY

330068 The EMF of the cell \(\left. {{\text{Ni}}} \right \vert \left. {{\text{N}}{{\text{i}}^{{\text{2 + }}}}} \right\vert \left. {{\text{C}}{{\text{u}}^{{\text{2 + }}}}} \right \vert {\text{Cu}}\left( {\text{s}} \right)\) is 0.59 volt. The standard reduction electrode potential of copper electrode is 0.34 volt. The standard reduction electrode potential of nickel electrode will be

1 –0.025 volt
2 –0.50 volt
3 0.25 volt
4 –0.25 volt
CHXII03:ELECTROCHEMISTRY

330069 The \({{\rm{E}}^{\rm{o}}}\) for the following cell is 0.34 V. \(\left. {{\rm{In(s)}}} \right \vert \left. {{\rm{In(OH}}{{\rm{)}}_{\rm{3}}}{\rm{(aq)}}} \right\vert \left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}{\rm{(aq)}}} \right \vert {\rm{Sb(s)}}\)
[Using \({{\rm{E}}^{\rm{o}}}{\rm{ = - 1}}{\rm{.0V}}\) for the \(\left. {{\rm{In(O}}{{\rm{H}}_{\rm{3}}}{\rm{)}}} \right \vert \) In couple, calculate \({{\rm{E}}^{\rm{o}}}\) for the \(\left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}} \right \vert {\rm{Sb}}\) half-reaction:]

1 \({\rm{ - 1}}{\rm{.34}}\)
2 \({\rm{ + 0}}{\rm{.66}}\)
3 \( + 0.82\)
4 \( - 0.66\)
CHXII03:ELECTROCHEMISTRY

330070 The standard electrode potential for the half cell reactions are
\({\rm{Z}}{{\rm{n}}^{{\rm{2 + }}}} + 2{e^ - } \to Zn;\,\,{E^o} = - 0.76\,\,V\)
\(F{e^{2 + }} + 2{e^ - } \to Fe;\,\,{E^o} = - 0.44\,\,V\)
The e.m.f of the cell reaction
\(F{e^{2 + }} + Zn \to Z{n^{2 + }} + Fe\)

1 \({\rm{ - 1}}{\rm{.20}}\,\,{\rm{V}}\)
2 \({\rm{ + 1}}{\rm{.20}}\,\,{\rm{V}}\)
3 \({\rm{ + 0}}{\rm{.32}}\,\,{\rm{V}}\)
4 \({\rm{ - 0}}{\rm{.32}}\,\,{\rm{V}}\)
KCET - 2009
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CHXII03:ELECTROCHEMISTRY

330066 The oxidation potentials of \({\rm{Zn,}}\,\,{\rm{Cu,}}\,\,{\rm{Ag,}}\,\,{{\rm{H}}_{\rm{2}}}\,\,{\rm{and}}\,\,{\rm{Ni}}\) are \({\rm{0}}{\rm{.76, - 0}}{\rm{.34, - 0}}{\rm{.80, 0}}{\rm{.00, 0}}{\rm{.25}}\) volt, respectively. Which of the following reactions will provide maximum voltage?

1 \({{\text{H}}_{\text{2}}}{\text{ + N}}{{\text{i}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Ni}}\)
2 \({{\text{H}}_{\text{2}}}{\text{ + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Cu}}\)
3 \({\text{Zn + 2A}}{{\text{g}}^{\text{ + }}} \to {\text{2Ag + Z}}{{\text{n}}^{{\text{2 + }}}}\)
4 \({\text{Zn + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{Cu + Z}}{{\text{n}}^{{\text{2 + }}}}\)
CHXII03:ELECTROCHEMISTRY

330067 If the half-cell reactions are given as
\({\rm{ I}}{\rm{. F}}{{\rm{e}}^{2 + }}({\rm{aq}}) + 2{{\rm{e}}^ - } \to {\rm{Fe(s)}},{\rm{E}}^\circ = - 0.44\;{\rm{V}}\)
\({\rm{II}}{\rm{. }}2{{\rm{H}}^ + }{\rm{(aq)}} + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} + 2{{\rm{e}}^ - } \to {{\rm{H}}_2}{\rm{O}}(l),\)
\(\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{E}}^\circ = + 1.23\;{\rm{V}}\)
then \({\rm{E}}^\circ \) for the reaction,
\({\rm{Fe(s)}} + 2{{\rm{H}}^ + } + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} \to {\rm{F}}{{\rm{e}}^{2 + }}{\rm{(aq)}} + {{\rm{H}}_2}{\rm{O}}({\rm{l}})\)

1 \(+1.67 \mathrm{~V}\)
2 \(-1.67 \mathrm{~V}\)
3 \(+0.79 \mathrm{~V}\)
4 \(-0.79 \mathrm{~V}\)
CHXII03:ELECTROCHEMISTRY

330068 The EMF of the cell \(\left. {{\text{Ni}}} \right \vert \left. {{\text{N}}{{\text{i}}^{{\text{2 + }}}}} \right\vert \left. {{\text{C}}{{\text{u}}^{{\text{2 + }}}}} \right \vert {\text{Cu}}\left( {\text{s}} \right)\) is 0.59 volt. The standard reduction electrode potential of copper electrode is 0.34 volt. The standard reduction electrode potential of nickel electrode will be

1 –0.025 volt
2 –0.50 volt
3 0.25 volt
4 –0.25 volt
CHXII03:ELECTROCHEMISTRY

330069 The \({{\rm{E}}^{\rm{o}}}\) for the following cell is 0.34 V. \(\left. {{\rm{In(s)}}} \right \vert \left. {{\rm{In(OH}}{{\rm{)}}_{\rm{3}}}{\rm{(aq)}}} \right\vert \left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}{\rm{(aq)}}} \right \vert {\rm{Sb(s)}}\)
[Using \({{\rm{E}}^{\rm{o}}}{\rm{ = - 1}}{\rm{.0V}}\) for the \(\left. {{\rm{In(O}}{{\rm{H}}_{\rm{3}}}{\rm{)}}} \right \vert \) In couple, calculate \({{\rm{E}}^{\rm{o}}}\) for the \(\left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}} \right \vert {\rm{Sb}}\) half-reaction:]

1 \({\rm{ - 1}}{\rm{.34}}\)
2 \({\rm{ + 0}}{\rm{.66}}\)
3 \( + 0.82\)
4 \( - 0.66\)
CHXII03:ELECTROCHEMISTRY

330070 The standard electrode potential for the half cell reactions are
\({\rm{Z}}{{\rm{n}}^{{\rm{2 + }}}} + 2{e^ - } \to Zn;\,\,{E^o} = - 0.76\,\,V\)
\(F{e^{2 + }} + 2{e^ - } \to Fe;\,\,{E^o} = - 0.44\,\,V\)
The e.m.f of the cell reaction
\(F{e^{2 + }} + Zn \to Z{n^{2 + }} + Fe\)

1 \({\rm{ - 1}}{\rm{.20}}\,\,{\rm{V}}\)
2 \({\rm{ + 1}}{\rm{.20}}\,\,{\rm{V}}\)
3 \({\rm{ + 0}}{\rm{.32}}\,\,{\rm{V}}\)
4 \({\rm{ - 0}}{\rm{.32}}\,\,{\rm{V}}\)
KCET - 2009
NEET DIGITAL LIBRARY
CHXII03:ELECTROCHEMISTRY

330066 The oxidation potentials of \({\rm{Zn,}}\,\,{\rm{Cu,}}\,\,{\rm{Ag,}}\,\,{{\rm{H}}_{\rm{2}}}\,\,{\rm{and}}\,\,{\rm{Ni}}\) are \({\rm{0}}{\rm{.76, - 0}}{\rm{.34, - 0}}{\rm{.80, 0}}{\rm{.00, 0}}{\rm{.25}}\) volt, respectively. Which of the following reactions will provide maximum voltage?

1 \({{\text{H}}_{\text{2}}}{\text{ + N}}{{\text{i}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Ni}}\)
2 \({{\text{H}}_{\text{2}}}{\text{ + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{2}}{{\text{H}}^{\text{ + }}}{\text{ + Cu}}\)
3 \({\text{Zn + 2A}}{{\text{g}}^{\text{ + }}} \to {\text{2Ag + Z}}{{\text{n}}^{{\text{2 + }}}}\)
4 \({\text{Zn + C}}{{\text{u}}^{{\text{2 + }}}} \to {\text{Cu + Z}}{{\text{n}}^{{\text{2 + }}}}\)
CHXII03:ELECTROCHEMISTRY

330067 If the half-cell reactions are given as
\({\rm{ I}}{\rm{. F}}{{\rm{e}}^{2 + }}({\rm{aq}}) + 2{{\rm{e}}^ - } \to {\rm{Fe(s)}},{\rm{E}}^\circ = - 0.44\;{\rm{V}}\)
\({\rm{II}}{\rm{. }}2{{\rm{H}}^ + }{\rm{(aq)}} + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} + 2{{\rm{e}}^ - } \to {{\rm{H}}_2}{\rm{O}}(l),\)
\(\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{E}}^\circ = + 1.23\;{\rm{V}}\)
then \({\rm{E}}^\circ \) for the reaction,
\({\rm{Fe(s)}} + 2{{\rm{H}}^ + } + \frac{1}{2}{{\rm{O}}_2}{\rm{(g)}} \to {\rm{F}}{{\rm{e}}^{2 + }}{\rm{(aq)}} + {{\rm{H}}_2}{\rm{O}}({\rm{l}})\)

1 \(+1.67 \mathrm{~V}\)
2 \(-1.67 \mathrm{~V}\)
3 \(+0.79 \mathrm{~V}\)
4 \(-0.79 \mathrm{~V}\)
CHXII03:ELECTROCHEMISTRY

330068 The EMF of the cell \(\left. {{\text{Ni}}} \right \vert \left. {{\text{N}}{{\text{i}}^{{\text{2 + }}}}} \right\vert \left. {{\text{C}}{{\text{u}}^{{\text{2 + }}}}} \right \vert {\text{Cu}}\left( {\text{s}} \right)\) is 0.59 volt. The standard reduction electrode potential of copper electrode is 0.34 volt. The standard reduction electrode potential of nickel electrode will be

1 –0.025 volt
2 –0.50 volt
3 0.25 volt
4 –0.25 volt
CHXII03:ELECTROCHEMISTRY

330069 The \({{\rm{E}}^{\rm{o}}}\) for the following cell is 0.34 V. \(\left. {{\rm{In(s)}}} \right \vert \left. {{\rm{In(OH}}{{\rm{)}}_{\rm{3}}}{\rm{(aq)}}} \right\vert \left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}{\rm{(aq)}}} \right \vert {\rm{Sb(s)}}\)
[Using \({{\rm{E}}^{\rm{o}}}{\rm{ = - 1}}{\rm{.0V}}\) for the \(\left. {{\rm{In(O}}{{\rm{H}}_{\rm{3}}}{\rm{)}}} \right \vert \) In couple, calculate \({{\rm{E}}^{\rm{o}}}\) for the \(\left. {{\rm{SbO}}_{\rm{2}}^{\rm{ - }}} \right \vert {\rm{Sb}}\) half-reaction:]

1 \({\rm{ - 1}}{\rm{.34}}\)
2 \({\rm{ + 0}}{\rm{.66}}\)
3 \( + 0.82\)
4 \( - 0.66\)
CHXII03:ELECTROCHEMISTRY

330070 The standard electrode potential for the half cell reactions are
\({\rm{Z}}{{\rm{n}}^{{\rm{2 + }}}} + 2{e^ - } \to Zn;\,\,{E^o} = - 0.76\,\,V\)
\(F{e^{2 + }} + 2{e^ - } \to Fe;\,\,{E^o} = - 0.44\,\,V\)
The e.m.f of the cell reaction
\(F{e^{2 + }} + Zn \to Z{n^{2 + }} + Fe\)

1 \({\rm{ - 1}}{\rm{.20}}\,\,{\rm{V}}\)
2 \({\rm{ + 1}}{\rm{.20}}\,\,{\rm{V}}\)
3 \({\rm{ + 0}}{\rm{.32}}\,\,{\rm{V}}\)
4 \({\rm{ - 0}}{\rm{.32}}\,\,{\rm{V}}\)
KCET - 2009