1. (F&H- 4.5) The purpose of this problem is to compare the limiting current for the electrorefining of Cu both with and without supporting electrolyte. Assume that copper us reduced at the left electrode (x=0) and oxidized at the right electrode (x=L). You should also assume steady state and no convection. Finally, assume that the current efficiency for both copper oxidation and reduction are 100%, (Note that the assumption of no convection leads to very Low values of the limiting current since transport by diffusion is slow over the 5 cm gap.

1. How do the two expressions compare? Why is the limiting current lower in the presence of a supporting electrolyte?