question_answer 33)

Predict the products of electrolysis in each of the following : (i) An aqueous solution of AgNO3 with silver electrodes. (ii) An aqueous solution of AgNO3 with platinum electrodes. (iii) A dilute solution of H­2SO4 with platinum electrodes. (iv) An aqueous solution of CuCl2 with platinum electrodes (Given E0Ag+ /Ag = + 0.80 V,

Answer:

(i) AgNO3  Ag+ + At cathode: silver is deposited Ag+ + e?  Ag At anode: The silver of the electrode is oxidized to Ag+ ions which go into the solution or NO3 ions dissolve equivalent amount of silver of the electrode. Ag  Ag+ + e? Ag + NO3? AgNO3 + e? (ii) With platinum electrodes (inert electrode) AgNO3  Ag+ +                    At cathode: The R.P. of Ag+/Ag is greater than Ag+/Ag is greater than H+/so silver ion gets reduced.   Ag+ + e? Ag At anode:   discharge potential of OH? is < discharge potential of NO3?, so the reaction taking place is (iii)     At anode: [ Discharge potential of OH? < Discharge potential of At cathode: 2H+ + 2e?   (iv) At anode: [ Discharge potential of Cl? < Discharge potential of OH?] At cathode: Cu2+ 2e?  Cu [ Reduction potential of Cu2+ > H+]