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This question is also already on the cramster site, but I don'tunderstand the answer.

Ch. 17 #73: What is the reduction potential at 25 C for thehydrogen electrode in each of the following solutions? The halfreaction is:

2H+ (aq) + 2 e- --> H2 (g, 1 atm)

E = E^ - 0.0592V/n x log pH2/[H+]^2
b.) a solution having pH = 4.00
Please explain why the number of moles of electrons (n) is 1and why in the worked answer, the concentration of hydrogen [10^-4]is not squared as the hydrogen concentration was for the halfreaction given.
i.e. answer: E = E^ - 0.0592V/1 x log (1/[10^-4}
So in short, why is n = 1 moles of electrons and why is it log(1/[10^-4]) and not log (1/[10^-4}^2)?
Thanks.

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