Describe the process for the extraction of chlorine.

(N/A) Chlorine is primarily extracted by the electrolysis of brine ($NaCl$ solution) in the Chlor-alkali process.
$1$. During electrolysis,$Cl^-$ ions are oxidized at the anode to form chlorine gas: $2Cl^- (aq) \rightarrow Cl_2 (g) + 2e^-$.
$2$. At the cathode,water is reduced to form hydrogen gas and hydroxide ions: $2H_2O (l) + 2e^- \rightarrow H_2 (g) + 2OH^- (aq)$.
$3$. The overall reaction is: $2NaCl (aq) + 2H_2O (l) \rightarrow Cl_2 (g) + H_2 (g) + 2NaOH (aq)$.