Question

During the chlor-alkali process, which gas is liberated​ at anode and cathode, respectively?

Answer 1

Caustic soda is prepared from common salt through a process called the Chlor-alkali process.
Electrolysis of brine yields:

• Sodium hydroxide solution at the cathodic side of the solution
• Chlorine gas at the anode.
• Hydrogen gas at the cathode.

Reactions involved:
$\text{2NaCl}\text{(s)}+2{\text{H}}_2\text{O}\text{(l)}\to {\text{Cl}}_2\text{(g)}+{\text{H}}_2\text{(g)}+2\text{NaOH (aq)}$