Autoprotolysis of water is not a redox reaction, but the free energy change of any reaction can still be expressed as a potential. Given Kw, calculate ΔG° and E° for the autoprotolysis of water. [Proton transfer reactions are one-electron processes, since the corresponding half-reaction would involve H+ and ½H2.] Why is it not possible for all species in this reaction to be in their standard states at equilibrium? Calculate E for this reaction in pure water at equilibrium.