Question

The standard electrode potential of Cu⁺²/Cu is +0.34 V and that of Cr⁺³/Cr is −0.74 V. These two electrodes are connected in their standard state to make an electrochemical cell. What will be the standard electrode potential (E°) of this cell?

Options

• 1.19 V

• 1.08 V

• 0.69 V

• 1.83 V

Answer 1

1.08 V

Explanation:

Given: \[\ce{E^{\circ}_{{Cu^{2+}/{Cu}}}}\] = +0.34 V (Reduction at cathode)

\[\ce{E^{\circ}_{{Cr^{3+}/{Cu}}}}\] = −0.74 V (Oxidation at anode)

We know that

\[\ce{E{^{\circ}_{cell}} = E{^{\circ}_{cathode}} - E{^{\circ}_{anode}}}\]

= 0.34 − (−0.74)

= 0.34 + 0.74

= 1.08 V