How is chlorine prepared by electrolytic method ? Explain its reaction with
`NH_(3)` under different conditions.

Explanation

Chlorine is obtained by the electrolysis of brine solution. Chlorine is liberated at anode.
Brine solution is taken in a perforated U-shaped steel vessel. Graphite rod acts as anode, steel vessel.acts as cathode. `H_(2)` and NaOH are by products .

` NaCl to Na^(+) + Cl^(-)`
At Anode : ` 2Cl - 2 e to Cl_(2)`
` 2 H_(2) O + 2 e to 2 OH ^(-) + H_(2)`
`Na^(+) + OH^(-) to NaOH`
Reactions :
i) With excess ammonia, Nitrogen gas is evolved
` 8 NH_(3) + 3Cl_(2) to 6 NH_(4) Cl + N_(2)`
ii) When chlorine is in excess, `NCl_(3)` and HCl are formed ,br> ` NH_(3) + 3Cl_(2) to NCl_(3) + 3 HCl`