In the solution of 6O.3, it says the standard reduction potential of water Enaught = -0.42V. What equation corresponds to this and how did they get this number? I can't seem to find it in the appendix.
I assumed reduction of water is 2e- + 2H2O -> H2 + 2OH- and oxidation is 2H2O -> O2 + 4H+ + 4e-. But in the appendix these correspond to Enaught = -0.83 and Enaught = +1.23.
Standard reduction potential of water
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Re: Standard reduction potential of water
ChihWei Chen 2C wrote:In the solution of 6O.3, it says the standard reduction potential of water Enaught = -0.42V. What equation corresponds to this and how did they get this number? I can't seem to find it in the appendix.
I assumed reduction of water is 2e- + 2H2O -> H2 + 2OH- and oxidation is 2H2O -> O2 + 4H+ + 4e-. But in the appendix these correspond to Enaught = -0.83 and Enaught = +1.23.
It seems -0.42 is pretty much half of 0.83 so is there a correlation there? I would like to figure out the answer to this as well.
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Re: Standard reduction potential of water
ChihWei Chen 2C wrote:In the solution of 6O.3, it says the standard reduction potential of water Enaught = -0.42V. What equation corresponds to this and how did they get this number? I can't seem to find it in the appendix.
I assumed reduction of water is 2e- + 2H2O -> H2 + 2OH- and oxidation is 2H2O -> O2 + 4H+ + 4e-. But in the appendix these correspond to Enaught = -0.83 and Enaught = +1.23.
Aditya Sundaram 3D wrote:ChihWei Chen 2C wrote:In the solution of 6O.3, it says the standard reduction potential of water Enaught = -0.42V. What equation corresponds to this and how did they get this number? I can't seem to find it in the appendix.
I assumed reduction of water is 2e- + 2H2O -> H2 + 2OH- and oxidation is 2H2O -> O2 + 4H+ + 4e-. But in the appendix these correspond to Enaught = -0.83 and Enaught = +1.23.
It seems -0.42 is pretty much half of 0.83 so is there a correlation there? I would like to figure out the answer to this as well.
At the top of the topic 6O Exercises section, there's a little blurb that says "base your answers on the potentials listed in appendix 2B, with the exception of the reduction and oxidation of water at pH=7. Reduction: E=-0.42V at pH=7, Oxidation E=+0.82V at pH=7"
I don't know exactly how E values change based off of pH, but the problem gives you those values at pH=7 to use :)
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