Question

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

Hint:

Remember: \textbf{A}node attracts \textbf{A}nions (\( Cl^- \rightarrow Cl_2 \)). \textbf{C}athode attracts \textbf{C}ations (\( H^+ \rightarrow H_2 \)).

Answer 1

Step 1: Understanding the Concept:
The chlor-alkali process is an industrial process used to produce sodium hydroxide, chlorine, and hydrogen from a concentrated solution of sodium chloride (brine).
Step 2: Detailed Explanation:
When electricity is passed through an aqueous solution of sodium chloride (brine), it decomposes to form sodium hydroxide. This process is called the chlor-alkali process because of the products formed: 'chlor' for chlorine and 'alkali' for sodium hydroxide.
Chemical Equation:
\[ 2NaCl(aq) + 2H_2O(l) \rightarrow 2NaOH(aq) + Cl_2(g) + H_2(g) \]
Products at Electrodes:
1. At the Anode (+): Chlorine gas (\( Cl_2 \)) is evolved.
2. At the Cathode (-): Hydrogen gas (\( H_2 \)) is evolved.
3. Sodium hydroxide (\( NaOH \)) solution is formed near the cathode.
Step 3: Final Answer:
The chlor-alkali process involves the electrolysis of brine to produce \( NaOH \), \( Cl_2 \), and \( H_2 \). Products: Chlorine at anode, Hydrogen at cathode.