Abstract:

The ion electric migration phenomenon in CuSO₄ electrolyte is investigated with Pt and Cu sheets as the electrodes, respectively. The electric migration process is qualitatively analyzed from the color change of the anodic and cathodic solutions before and after the electrolysis. The effect of the electrolyte concentration on the ion transference number is analyzed through the change of the mass of Cu electrodes and the change of the concentration of CuSO₄ solution. By using different electrodes, the electrochemical reactions on the anodes and cathodes are also discussed. This improvement on the ion transference number measurement by Hittorf method aims to deepen the students' understanding of ion electric migration phenomenon by making comparisons of the electrode reactions in different electrolytes with different electrodes.

Key words: Hittorf method, Ion transference number, Electro-migration phenomenon, Electrode reaction