Name the processes from which chlorine is obtained as a by-product. What will happen if an aqueous solution of NaCl is subjected to electrolysis?

Explanation

(i) Chlorine is obtained as a by product during electrolysis of sodium chloride by Down.s process for the manufacture of sodium.
`NaCl(l) overset("Electrolysis")to Na^(+) ` (melt) + `Cl^(-)` (melt)
At anode : `Cl^(-) ` (melt) `to Cl(g) + e^(-)`
`" " Cl (g) + Cl (g) to Cl_2 (g)`
At cathode : `Na^(+) ` (melt)+ `e^(-) to Na (s)`
(ii) Electrolysis of brine solution in Castner Kellner cell for manufacturing soldium hydroxide (caustic soda).