Question

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.

Answer 1

i)Reaction in solution:AgNO3  -------------------------------à Ag + + NO =3             H2O=====================èH+   +OH-:Reaction at cathode:Ag++    e-----------------------------------à Ag:Reaction at Anode: Ag( s )     + NO-3--------------------------------à  AgNO3  (Aq)   +e:Hence Ag will deposit at cathode and dissolve at anode:

ii) Reaction at solution:AgNO3-------à Ag ++ NO-3       H2O======================è H+     +OH=:Reaction at cathode         Ag ++e--------------------------------à Ag:Reaction ay anode:Due to platinum electrode salt of ionisation of water will take place:H2O  --à2H++ ½ O2 ( G ) + 2e.

Hence H2 gas will be generated at cathode and O2 at anode.1)Reaction in solution:CuCl2 ( s ) -----------------à Cu2++ 2e,H2O---------à H+   + OH-,Reaction at cathode ,Cu2++2e-----àCu(S ),Reaction at anode ,2Cl----------------àCl2+2e.Hence Cu that is metallic copper will deposit at cathode and Cl2 gas will be generatedat anode.