Which gas is formed at the cathode in the chlor-alkali process?
Answer and explanation
Correct answer: Hydrogen
In the chlor-alkali process, brine is electrolysed. Water molecules gain electrons at the cathode and are reduced, producing hydrogen gas and hydroxide ions: 2H₂O + 2e⁻ → H₂ + 2OH⁻. Hence hydrogen is formed at the cathode. Chlorine is produced at the anode, whereas nitrogen and sulphur dioxide are not products of brine electrolysis. Hydrogen may be identified by its characteristic pop sound.
Frequently asked questions
What is the correct answer to this question?
Hydrogen
Why is this the correct answer?
In the chlor-alkali process, brine is electrolysed. Water molecules gain electrons at the cathode and are reduced, producing hydrogen gas and hydroxide ions: 2H₂O + 2e⁻ → H₂ + 2OH⁻. Hence hydrogen is formed at the cathode. Chlorine is produced at the anode, whereas nitrogen and sulphur dioxide are not products of brine electrolysis. Hydrogen may be identified by its characteristic pop sound.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
