Determination of Heterogeneous Equilibrium Constants by Chemical Stripping at a Ring-Disk Electrode Evaluation of the Equilibrium Constant for the Reaction Copper + Copper(II) →2 Copper(I) in 0.2m Sulfuric Acid

A general theory and experimental procedure for the determination of heterogeneous equilibrium constants using a ring-disk electrode is presented. The equilibrium constant for the reaction Cu + Cu(II) → Cu(I) was measured by this technique and found to be 5.6 10^-7. The value determined by chemical stripping was in agreement with the value determined by equilibrating copper with Cu(II). The values for the diffusion coefficients of Cu(I), Cu(II), and Ag(I) in 0.2M H₂SO₄ were found to be 13.8, 5.7, and 13.7 X 10^-6 cm²/sec, respectively.