2. (a) Draw schematic diagrams of the current obtained at a platinum electrode when the potential is scanned from 600 to -200 and back to 600 mV (i) in a solution containing 0.1 M KCI (ii) in a solution containing the reversible redox couple, Co(phen)32 at a concentration of 1 mM and KC1 (0.1 M) 2+/3+ Co(phen)33++ e¯ Co(phen) 32+ Eº = 0.1 V (iii) (iv) Describe and explain the features of the current and potential obtained in both cases. Estimate the double layer capacitance of the electrode solution interface given that the current in a solution containing 0.1 M KCl was constant with a value of 0.5 µA, over the potential range 100 to 200 mV. The scan rate was 20 mV s¨¹.