r0749547
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standard electrode potential of acetate
Does anyone know the standard electrode potential of this half reaction?:
2 CH3COO- <-> C2H6 + 2 CO2 + 2 e-
I've tried to google it but I can only find the standard electrode potential of formate and oxalate...
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unionised
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Electrode potentials are only meaningful for reversible reactions.
That one isn't, so the potential is undefined.
You might be able to find the potential for CH3COO- → CH3COO· +e-
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WGTR
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Keep in mind there is also an electrode overvoltage to contend with, and this will vary based on electrode material, it’s surface preparation,
temperature, current density, and ionic species/depolorizing agents present.
For something like Kolbe electrolysis, I have used a graphite anode in a refrigerated electrolyte, with pulsed high current to keep the oxygen
overvoltage high to minimize side products.
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r0749547
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so how do I know what would rather be oxidated during electrolysis?
(CH3COO- or H20 or for example Fe2+ or Cu+)
[Edited on 21-12-2018 by r0749547]
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kmno4
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Quote: Originally posted by r0749547 | Does anyone know the standard electrode potential of this half reaction?:
2 CH3COO- <-> C2H6 + 2 CO2 + 2 e-
I've tried to google it but I can only find the standard electrode potential of formate and oxalate... |
This reaction contains electrochemical step, given by unionised and non-electrochemical steps (destruction of radicals).
You may read these papers (besides of many other ones):
Anode phenomena in the electrolysis of potassium acetate solutions. Part II. Discharge potential of the acetate ion (DOI:10.1039/TF9312700722)
Studies on the Kolbe Electrolytic Synthesis. IV. A Theoretical Investigation of the Mechanism by Standard Potential Calculations.
(DOI: 10.3891/acta.chem.scand.17-2004)
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r0749547
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Ok thanks
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