Talk:Absolute electrode potential

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Absolute and relative potentials[edit]

I undid an edit (and then accidentally undid the undo, and then undid that), where the definition of the absolute potential was given as -E_abs = E_relative + 4.44. However, the article says that the absolute potential of the SHE is 4.44 eV, meaning this definition becomes

E_absSHE + E_absM = -E_relative.

This definition cannot be correct, because rather than canceling the arbitrary constant in the indefinite integral that gives you an electric potential, the left hand side contains a sum of the two constants. Even if E_abs is defined as the potential relative to the potential at infinity, E_relative needs to be defined as the difference between two absolute potentials, not the sum, so something like

E_absM - E_absSHE = E_relative

Which is equivalent to the equation as it is currently defined after undoing the revision. Since I'm not extremely knowledgable about electrochemistry, I'll leave it to someone else to make sure that the article is correct stating that 4.44 is the absolute potential of the SHE and not minus the absolute potential of the SHE. Also, for all I know, there may be a silly minus sign somewhere in the definition, but that still wouldn't reduce to the first equation I wrote, because the two values on the left hand side must have opposite sign. Mpalenik (talk) 22:07, 19 July 2016 (UTC)