Cu-Zn Ice tray battery: 2 possible cathodes?: the piece of Copper OR the liquid in which is plunged the Zinc nail?

This is the ice-tray battery:


[![ice-tray battery](https://i.stack.imgur.com/73jJN.png)](https://i.stack.imgur.com/73jJN.png)


Nails are in Zinc, wrapped with Copper wire.
The Copper wire and the Zinc nails are each plunged into white vinegar (8% acidity).


So I see 2 possible ways to consider what is the cathode here:


* Electrons are ripped from Zinc. They flow until the Copper wire, where, reaching the liquid in which is plunged the Copper wire, the electrons are given to the H+ of the white vinegar and form hydrogen gas.


**So the cathode is the piece of Copper, the anode is the zinc nail.**
* OR: like it's shown on the picture (one leg of the LED plunged into the liquid in which is plunged the Zinc nail and the other into the liquid in which is plunged the Copper wire).


The liquid in which is plunged the Copper wire loses H+ (which are forming Hydrogen gas): So it's more negative. On the other side, the liquid in which is plunged the Zinc nail gets an accumulation of Zn2+ ions which dissolved in it. So it's more positive.


**So the cathode is the liquid in which the Zinc nail is plunged, and the anode the liquid in which the copper wire is plunged.**


Is that true?




OK, some details, on this galvanic cell construction where, [this reference](https://www.stevespanglerscience.com/lab/experiments/ice-tray-battery/) cites the following step, to quote:



> 
> Tightly wrap a piece of copper wire five times around a galvanized nail just under the head of the nail.
> 
> 
> 


So, as "galvanized" means Zinc coated, iron is not actually (at least at the start) part of this galvanic cell.


As such, without doubt the highly anodic Zinc is the anode, leaving either copper or air (oxygen) as possible cathodes (or a cathodic zone).


Another instruction:



> 
> You’ll create a circuit by placing each nail into one well of vinegar and making sure the copper wire is bent so that it goes into the vinegar in the next well. The wire is an electron bridge from one well into the next. Make sure the wire from one nail does NOT touch the nail or wire in any other well. There should be only vinegar between the metals in each well.
> 
> 
> 


And finally:



> 
> Place one “leg” of the LED into the well with only a copper wire inside it and place the other “leg” into the well with only a nail in it. If the bulb lights up, you nailed it! If the bulb doesn’t light up, just lift the bulb out of the well, rotate it a half-turn to move the legs to the opposite well, and lower it back into the vinegar. It lights up!
> 
> 
> 


The provided explanation on the functioning of the cell asserts:



> 
> The two metal components are electrodes. They’re the sites in a battery where moving electrons (the current) enter and then leave the battery. With this vinegar, zinc, and copper set-up, the current will flow from the wire bridge (copper), across the vinegar, to the nail (zinc), and then along the bridge to the vinegar and… well, you get the idea. The electricity passes easily through the acidic solution of vinegar in the wells.
> 
> 
> 


So, copper is the anode to answer your question.


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