Which of the following happen(s) at the cathode of this cell? CHEM!!!?

Question

An electrolytic cell is made with zinc and aluminum electrodes. Which of the following happen(s) at the cathode of this cell?

More then one answer so please say all that apply!

A. Aluminum ions are formed.

B. Solid aluminum is formed.

C. Zinc is oxidized.

D. Aluminum is reduced.

E. Zinc ions are formed.

Answer 1

First you have to decide what reaction is taking place.

The reduction potentials are:

Al3+ + 3e-  ==>  Al . . . .Eo = -1.66 V

Zn2+ + 2e-  ==>  Zn . . .Eo = -0.76 V

One of the above reactions is a reduction and the other is an oxidation (occurs in the opposite direction). So if Al3+ is reduced, Eo cell = -1.66 V + 0.76 V = -0.90 V. That's an electrolytic cell because it has a negative potential and must be hooked to a battery to make it occur.

2Al3+  +  3Zn  ==>  2Al  +  3Zn2+

If Zn2+ were being reduced, then Eo = +1.66 V - 0.76 V = +0.90 V. That's a galvanic cell (positive Eo) so that's not it.

In any cell (galvanic or electrolytic), reduction occurs at the cathode. In our case the reduction reaction is Al3+ going to Al. So the answer is D.

Answer 2

aluminum is reduced, solid aluminum is formed. that's all.

i think there is no aluminum ions here.

option C and the rest can't be true since oxidation occurs in anode.