Which gas is formed at the cathode in the chlor-alkali process?
Answer and explanation
Correct answer: Hydrogen
The governing concept is reduction at the cathode during brine electrolysis. At the cathode, water gains electrons and produces hydrogen gas and hydroxide ions: 2H₂O + 2e⁻ → H₂ + 2OH⁻. Chlorine is formed at the anode by oxidation of chloride ions. Nitrogen and sulphur dioxide are not products of the chlor-alkali process. Hence, the gas formed at the cathode is hydrogen, so option A is correct.
Frequently asked questions
What is the correct answer to this question?
Hydrogen
Why is this the correct answer?
The governing concept is reduction at the cathode during brine electrolysis. At the cathode, water gains electrons and produces hydrogen gas and hydroxide ions: 2H₂O + 2e⁻ → H₂ + 2OH⁻. Chlorine is formed at the anode by oxidation of chloride ions. Nitrogen and sulphur dioxide are not products of the chlor-alkali process. Hence, the gas formed at the cathode is hydrogen, so option A is correct.
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.
