Points to Remember:

• The potential of the polarized cathode is smaller than the potential of reversible electrode (h = 0). .The figure below shows the polarization of zinc.

h_c < h_eq

• The potential of the polarized anode is greater than the potential of reversible electrode

h_a > h_eq

h_cell > h_eq

FACTORS AFFECTING POLARIZATION

1. Current: Polarization will increase with increasing current

2. Area: The larger the area, the smaller would be the polarization

3. Temperature: The higher the temperature, the lower is the polarization

4. Agitation: The higher the agitation, the higher is the polarization

5. Concentration: For cathodic reactions involving dilute electrolytes polarize rapidly. In anodic reactions, polarization is the highest with concentrated electrolyte.