Question

Explain chlor-alkali process with chemical equation. Name the products formed at anode and cathode.

Answer 1

When electricity passes through an aqueous solution of sodium chloride (brine), it undergoes decomposition to form sodium hydroxide. This procedure is termed the chlor-alkali process due to the resultant products, ‘chlor’ for chlorine and ‘alkali’ for sodium hydroxide.

\[\ce{2NaCl_{(aq)} + 2H2O_{(l)} -> 2NaOH_{(aq)} + Cl2_{(g)} + H2_{(g)}}\]

Chlorine gas (Cl₂) is evolved at the anode, and hydrogen gas (H₂) is evolved at the cathode.