A area cm2 absorbance none C capacitance F concentration M, mol/cm3 D diffusion coefficient cm2/sec E emf of a reaction V potential vs reference V D E difference in potentials mV E° standard potential of an electrode V standard emf of a half-reaction V D E° difference in standard potentials V, mV for two couples E° ¢ formal potential V Ep peak potential V D Ep |Epa - Epc| in CV V, mV Epa anodic peak potential V Epc cathodic peak potential V ei input voltage V, mV eo output voltage V, mV F the faraday, the charge one mole C of electrons f F/RT V-1 G Gibbs free energy kJ D G Gibbs free energy in a chemical kJ process D G° standard Gibbs free energy kJ change in a chemical process H enthalpy kJ/mol D H enthalpy change in a chemical kJ process D H° standard enthalpy change in kJ chemical process i current A, m A ip peak current A, m A K equilibrium constant none k° heterogeneous rate constant cm/sec n number of electrons O oxidized form of O + ne- Û R none R reduced form of O + ne- Û R none gas constant J mol-1K-1 resistance W D S entropy change in a chemical kJ/K process D S° standard entropy change in kJ/K a chemical process T absolute temperature K v linear potential scan rate V/sec Z impedance W a transfer coefficient none d "diffusion layer" thickness Å h overpotential, E - Eeq V, mV y dimensionless rate parameter none |