Quinone undergoes a reversible reduction at a voltammetric working electrode. The reaction is
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(a) Assume that the diffusion coefficient for quinone and hydroquinone are approximately the same and calculate the approximate half-wave potential (versus SCE) for the reduction of hydroquinone at an ROE from a solution buffered to a pH of 7.0.
(b) Repeat the calculation in (a) for a solution buffered to a pH of 5.0.