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^(-) A mixture containing chlorides of sodium, calcium and zinc is electrolysed in presence of water The product obtained at cathode will be

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^(-) A mixture containing chlorides of sodium, calcium and zinc is electrolysed in presence of water The product obtained at cathode will be
Answer» NaCl `H_(2)` `CA` Zn Solution :The discharge POTENTIAL of `Na^(+),Ca^(+2),Zn^(+2)` ions is GREATER than discharge potential of `H^(+)` `:. H_(2)` gas is obtained at cathode. Cathode reaction is `2H_(2)O+2e^(-) to H_(2)+2OH^(-)`