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I drew a rough picture of the two cells, and marked each position with a distinct letter:enter image description here

The whole reason I am asking this question is that I am bit confused and unsure about some of the chemistry and physics concepts. It will be extremely helpful if you guys can tell me if what I did is correct and why.

What I think is correct: to make this whole thing work.

    1. Connect alligator clip x to position A, right on the zinc anode not the wire.
    1. And connect clip y to B, on the copper cathode plate.

From what I read, the electron is forced from Ag plate, anode, through the wire (with two alligator clips on each end), then reduces $Ag_{+}$ ions to $Ag$ metal on the spoon cathode. But from the picture, it looks more like all the electrons came from the zinc anode of the voltaic cell and all the electrons from the $Ag$ anode of the electrolytic cell go to $Cu$ cathode of the voltaic cell.

Some physics aspect of this: if x clip was to be connected to position C and y clip to position D, is it true that there will be no potential difference?(unless the wire itself has a high resistance)

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Let's start with the last question: The points A and C have the same potential, because we generally neglect the resistance of the wire. The same argument is valid for points B and D. But according to your scheme, you have a short circuit (as C and D are connected).

Now, to electroplate the spoon, you want the silver to be oxidized at the silver electrode. So, silver electrode is the anode, and must be connected to pole (+) of the voltaic cell (point B): $$\ce{Ag -> Ag+ + e- }$$ The spoon is the electrode where ion silver will be reduced. So, it's the cathode and must be connected to pole (-) of of the voltaic cell (point A). The electrons enter the cathode and reduced the silver ion according to the equation: $$\ce{Ag+ + e- -> Ag}$$

So, you're right!

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  • $\begingroup$ What is short cutting? Do you mean short circuit (actually it doesn't make too much sense)? What do mean exactly by "short cutting"? $\endgroup$ – most venerable sir Apr 11 '15 at 0:05
  • $\begingroup$ I mean short circuit and this occurs because the positive and negative terminals of the battery are connected with a wire. In fact,due to the low resistance in the connection, a high current exists, causing the cell to deliver a large amount of energy in a short time. $\endgroup$ – Yomen Atassi Apr 11 '15 at 5:11
  • $\begingroup$ If AC have the same potential CD should also do. $\endgroup$ – most venerable sir Apr 17 '15 at 21:12
  • $\begingroup$ Electrolysis is always carried out using direct current because here the electrodes have definite polarity. Generally low voltage and high current are preferred. Towards A.C the behavior of the solution depends mainly on the electrodes. For most metallic electrodes namely Cu, Zn the solution behaves much like resistance and the energy is wasted in heating of the solution. $\endgroup$ – Yomen Atassi Apr 18 '15 at 6:46

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