While we could analyze Eq. 7c further using an arbitrary number of transferred electrons, it is best to limit ourselves to the transfer of one electron (𝑧 = 1) where it leads to clearer relationships. Moreover, there is no evidence to the existence of the simultaneous transfer of more electrons to an electrode. This yields Eq. 9a with the standard rate constant 𝑘 ⊖ (Eq. 9b). Here, two new quantities are introduced, 𝜆 and 𝜇.