A solution containing `Na^(o+),NO_(3)^(c-), Cl^(c-)`, and `SO_(4)^(2-)` ions, all at unit concentrations, is electrolyzed between nickel anode and platinum cathode. As the current is passed through the cell

Options

A. `Ph` of the cathode increases
B. Oxygen is the major product at anode
C. Nickel is deposited at cathode.
D. Chlorine is the major product at anode.

Answer

a,d

Explanation

`a.` At cathod `:` Reduction of `Na^(o+)` does not occur but reduction of `H_(2)O` occurs to give `overset(c-)(O)H` and `H_(2)(g)` , so `pOH` decreases and `pH` increases.
At anode `:` Oxidation of `Cl^(c-)` ions occur to give `Cl_(2)(g)`. Likewise, oxidation of `NO^(c-)._(3)` and `SO_(4)^(2-)` does not occur but oxidation of `H_(2)O` occuts to give `H^(o+)` ions and `H_(2)(g)`. So `pH` decreases at anode.