Voltaic (Daniell) Cell: Zinc Oxidation Explained

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SUMMARY

The discussion centers on the oxidation of zinc in a Daniell cell, emphasizing that zinc undergoes spontaneous oxidation regardless of the presence of a copper half-cell. Participants clarify that zinc loses electrons, leading to a reduction in the zinc rod's size, while copper can also lose electrons but is reduced when connected to zinc due to its lower oxidation potential. The conversation highlights the importance of the electrochemical series in understanding these reactions and questions the reliance on the Standard Hydrogen Electrode for measuring redox potentials.

PREREQUISITES
  • Understanding of electrochemical cells, specifically the Daniell cell.
  • Knowledge of oxidation and reduction reactions.
  • Familiarity with the electrochemical series and standard reduction potentials.
  • Basic concepts of spontaneous reactions in chemistry.
NEXT STEPS
  • Research the electrochemical series and its implications for redox reactions.
  • Study the Standard Hydrogen Electrode and its role in measuring redox potentials.
  • Explore the principles of spontaneous reactions in electrochemistry.
  • Investigate the behavior of half-cells in redox chemistry experiments.
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Chemistry students, educators, and researchers interested in electrochemistry, particularly those studying redox reactions and the behavior of metals in electrochemical cells.

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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