MHT CET202527 Apr 2025Evening ShiftChemistryElectrochemistryActual
Which among the following is common for electrolysis of molten NaCl and aqueous NaCl ?
Options
- AH _ 2( ~g ) is liberated at cathode.
- BNa _ ( s ) is collected at cathode.
- CNaCl is converted to NaOH _ ( aq ) .
- DCl ₂ gas is liberated at anode.
Correct answer
A. H _ 2( ~g ) is liberated at cathode.
Step-by-step solution
Electrolysis of molten and aqueous NaCl share only one common product: chlorine gas evolved at the anode. For molten NaCl, the only ions present are Na ^+ and Cl ^- . Reduction of Na ^+ occurs at the cathode: Na ^+ + e ^- → Na (s) . Oxidation of Cl ^- occurs at the anode: 2Cl ^- → Cl 2(g) + 2e ^- . For aqueous NaCl, the system contains Na ^+ , Cl ^- , H ^+ , and OH ^- . At the cathode, water is reduced instead of sodium due to its higher reduction potential: 2H 2 O + 2e ^- → H 2(g) + 2OH ^- . At the anode, chlorine