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Exchange Current Density of Metal Ions

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The following data were obtained for the reduction of metal ions A+ to metal A in a stirred solution at a 0.1 cm^2 electrode; the solution contained 0.01M A+.

n(mV) -100 -120,-150, -180, -220, -280, -370, -500, -600
i(uA) -45.9, -62.6, -100, -170, -300, -510, -770, -965, -965

Calculate the exchange current density jo[uA/cm^2], the symmetry factor, Beta, and the thickness of the diffusion layer, delta[cm], knowing the diffusion coefficient, D(A+)=1.3 x 10^-5 cm^2/s. What will be the surface concentration of A+[M], c^s A+, at overpotential of -280 mV?

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Solution Summary

This solution contains step-by-step calculations to determine the exchange current density, symmetry factor, beta, thickness of diffusion, delta and surface concentration. In addition, a Tafel plot is included to illustrate the trends in the data.

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