What is the correct order of gases formed at anode and cathode in the chlor-alkali process?
Answer and explanation
Correct answer: Chlorine and hydrogen
The governing concept is electrolysis of concentrated brine, an aqueous solution of sodium chloride. At the anode, chloride ions lose electrons and form chlorine gas: 2Cl− → Cl2 + 2e−. At the cathode, water is reduced and produces hydrogen gas: 2H2O + 2e− → H2 + 2OH−. Therefore the order anode then cathode is chlorine and hydrogen, so option A is correct.
Frequently asked questions
What is the correct answer to this question?
Chlorine and hydrogen
Why is this the correct answer?
The governing concept is electrolysis of concentrated brine, an aqueous solution of sodium chloride. At the anode, chloride ions lose electrons and form chlorine gas: 2Cl− → Cl2 + 2e−. At the cathode, water is reduced and produces hydrogen gas: 2H2O + 2e− → H2 + 2OH−. Therefore the order anode then cathode is chlorine and 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.
