Question 1
The half-reaction occurring at the cathode during electrolysis of an aqueous copper(II) iodide solution is
◦ I
2 + 2e
–→ 2I
–.
◦ Cu → Cu
2+ + 2e
–.
◦ Cu
2+ + 2e
–→ Cu.
◦ 2I
– → I
2 + 2e
–.
◦ 2e
– + 2H
2O → H
2 + 2OH
–.
Question 2
The half-reaction that occurs at the cathode during electrolysis of an aqueous sodium iodide solution is
◦ Na
+ + e
–→ Na.
◦ Na → Na
+ + e
–.
◦ 2H
2O + 2e
–→ H
2 + 2OH
–.
◦ I
2 + 2e
–→ 2I
–.
◦ 2I
–→ I
2 + 2e
–.