Question

A standard galvanic cell is constructed in which a Ni2+ | Ni half cell acts as the cathode. Which of the following statements are correct? (choose all that apply)

1. As the cell runs, anions will migrate from the Ni2+|Ni compartment to the other compartment.
2. The anode reaction could be Cr -> Cr3+ + 3e-
3. Ni2+ is reduced at the cathode.
4. The anode compartment could be I2|I-.
5. Ni is oxidized at the cathode.

Answer 1

Ni2+ is reduced at the cathode.

The anode reaction could be Cr -> Cr3+ + 3e-

As the cell runs, anions will migrate from the Ni2+|Ni compartment to the other compartment.

Step-by-step explanation:

As we know, in a galvanic cell, oxidation occurs at the anode and reduction occurs at the cathode. Hence at the cathode, nickel is reduced as follows;

Ni^2+(aq) + 2e ----> Ni(s)

Considering the reduction potential of the Ni2+ | Ni half cell (-0.25 V) and that of the Cr3+/Cr half cell (-0.74 V), the later has a more negative reduction potential and will most likely serve as the anode of the galvanic cell.

Lastly, the reduction of Ni^2+ leads to a build up of anions in the cathode compartment. To maintain neutrality in the cell, some anions migrate to the other compartment.