Question

A voltaic cell consists of a nickel electrode in a solution containing Ni2+ ions, and a copper electrode in a solution containing Cu2+ ions. Which is the cell potential? a. E subscript c e l l space end subscript superscript 0 space end superscript equals minus 0.59 V b. E subscript c e l l space end subscript superscript 0 space end superscript equals plus 0.59 V c. E subscript c e l l space end subscript superscript 0 space end superscript equals minus 0.09 V d. E subscript c e l l space end subscript superscript 0 space end superscript equals plus 0.09 V

Answer 1

First, we write the half equations for the reduction of the chemical species present:

Cu⁺² + 2e → Cu; E° = 0.34 V
Ni⁺² + 2e → Ni; E° = - 0.23 V

In order to determine the potential of the cell, we find the difference between the two values. For this:

E(cell) = 0.34 - (-0.23)
E(cell) = 0.57 V

The second option is correct. (The difference in values is due to different values in literature, and it is negligible)