The Total solution for NCERT class 6-12
Three electrolytic cells A,B,Ccontaining solutions of ZnSO4, AgNO3 and CuSO4,respectively are connected in series. A steady current of 1.5 amperes waspassed through them until 1.45 g of silver deposited at the cathode of cell B.How long did the current flow? What mass of copper and zinc were deposited?
Answer - 31 : -
According to the reaction:
Answer - 32 : -
(i) Fe3+(aq)and I−(aq)
(ii) Ag+ (aq)and Cu(s)
(iii) Fe3+ (aq)and Br− (aq)
(iv) Ag(s) andFe3+ (aq)
(v) Br2 (aq)and Fe2+ (aq).
Answer
Predict the products ofelectrolysis in each of the following:
Answer - 33 : -
(ii) An aqueous solution of AgNO_3with platinum electrodes.
(iii) A dilute solution of H_2SO_4with platinum electrodes.
For dilute sulphuric acid,reaction (i) is preferred to produce O2 gas. But forconcentrated sulphuric acid, reaction (ii) occurs.
(iv) Atcathode:
The following reduction reactionscompete to take place at the cathode.
At the anode, the reaction with alower value of is preferred. But due tothe over-potential of oxygen, Cl− gets oxidized at the anode toproduce Cl2 gas.