Voltaic (Daniell) Cell: Zinc Oxidation Explained

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The discussion centers on the oxidation of zinc in a Daniell cell and the spontaneous nature of this reaction. It is explained that zinc loses electrons even when not connected to a copper half-cell, as evidenced by the thinning of the zinc rod in a zinc chloride solution. The oxidation potential of zinc is greater than that of copper, leading to zinc being oxidized while copper is reduced when connected. Questions arise regarding the movement of electrons in a hypothetical setup and the reliance on the Standard Hydrogen Electrode (SHE) for measuring redox potentials, highlighting a lack of absolute measurements in redox chemistry. Additionally, there is skepticism about the observable dissolution of disconnected zinc and copper strips in the lab, suggesting that such reactions may take a significant amount of time.
gracy
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Me and one of my friend had a discussion about daniell cell my friend raised a doubt why does zn electrode gets oxidised without any reason?I answered her because it is spontaneous reaction.even if you will take only zinc beaker and zinc rod dipped in it zinc will lose electrons this is marked while doing experiment as zinc rod becomes thinner and shorter.so it is not that copper half cell is connected that's why zinc loses electron even without copper zinc does http://so.it/ is to be noted that copper also loses electron when not connected with zinc but when gets connected with zinc by conducting wire zinc has greater oxidation potential as compared to copper (go through electrochemical series )so zinc wins and gets oxidized, as oxidation can not occur alone there has to be reduction so copper gets reduced .
.Am i right?
 
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Not trying to insult you, but your posts will be much easier to read if you refrain from posting one long sentence.

I have two questions for you assuming I understood your post.

1. In your hypothetical metallic zinc bar + ZnCl2 setup, where would the electrons go?

2. If you are correct in your assumptions, it may be expected that we can simply use half cells to do redox chemistry, measure currents and so on. Why then do we have no absolute measurements of redox potentials but instead rely on something like the Standard Hydrogen Electrode (SHE) arbitrarily set to zero for our tables of standard reduction potentials?
 
gracy said:
if you will take only zinc beaker and zinc rod dipped in it zinc will lose electrons this is marked while doing experiment as zinc rod becomes thinner and shorter.so it is not that copper half cell is connected that's why zinc loses electron even without copper zinc does http://so.it/
During your lab class you noticed some of the disconnected zinc rod disolved in zinc chloride solution? I doubt it. Maybe over a period of weeks some of it might.

You also saw some of the isolated copper strip dissolve away, too? Over what period of time did you observe this?
 
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Yanick said:
Not trying to insult you
There is nothing to feel insulted.
 
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