Any help is appreciated in explaining the answer of this question:
Which one of the following reactions must be carried out in an electrolytic cell, rather than in an electrochemical cell?
Zn2+ + Ca –> Zn + Ca2+
Al3+ + 3Br– –> Al + (3/2)Br2
2Al + 3Fe2+ –> 2Al3+ + 3Fe
H2 + I2(s) –> 2H+ + 2I–
Thank you.