Electrolysis is an important technique for extraction of metals and each low of the solution needs a minimum voltage to get discharged and this value is expressed in terms of discharge potential. For some metal ions the discharge potentials follow the order give below : Li^(+) gt K^(+) gt Ca^(2+) gt Na^(+) gt Mg^(2+) gt Al^(3+) gt Zn^(2+) gt Fe^(2+) gt Ni^(2+) gt H_(3)O^(+) gt Cu^(2+) gt Hg_(2)^(2+) gt Ag^(+) gt Au^(3+) For some anions the discharge potentials are in the order: SO_(4)^(2-) gt NO_(3)^(-) gt OH^(-) gt Br^(-) gt I^(-) When aqueous NaCl is electrolysed by using Hg electrode, the product obtained at cathode is

Electrolysis is an important technique for extraction of metals and ea

1.	Electrolysis is an important technique for extraction of metals and each low of the solution needs a minimum voltage to get discharged and this value is expressed in terms of discharge potential. For some metal ions the discharge potentials follow the order give below : Li^(+) gt K^(+) gt Ca^(2+) gt Na^(+) gt Mg^(2+) gt Al^(3+) gt Zn^(2+) gt Fe^(2+) gt Ni^(2+) gt H_(3)O^(+) gt Cu^(2+) gt Hg_(2)^(2+) gt Ag^(+) gt Au^(3+) For some anions the discharge potentials are in the order: SO_(4)^(2-) gt NO_(3)^(-) gt OH^(-) gt Br^(-) gt I^(-) When aqueous NaCl is electrolysed by using Hg electrode, the product obtained at cathode is
Answer» NA-Hg amalgam Na `H_(2)` Hg Solution :In th presence of Hg the discharge potenetial of `Na^(+)` decreases and it dcharged FIRST. `2NaCl to 2Na^(+)+2Cl^(-)` At Anode `: 2Cl to Cl_(2)+2e^(-):` Ato CATHODE `Na^(+)+Hg+e^(-) to Na-Hg` Sodium amalaga.