Electrolysis of molten salts produces metal at cathode and non-metal at anode

Steps:

• Identify ions in molten MgCl₂: Mg²⁺ cations and Cl⁻ anions.
• At cathode (negative electrode), cations gain electrons: Mg²⁺ + 2e⁻ → Mg (magnesium metal).
• At anode (positive electrode), anions lose electrons: 2Cl⁻ → Cl₂ + 2e⁻ (chlorine gas).
• No water present in molten state, so no hydrogen or oxygen formed.

Why A is correct:

• Follows reduction of cation to metal at cathode and oxidation of anion to halogen at anode, per Faraday's laws of electrolysis.

Why the others are wrong:

• B: Hydrogen forms in aqueous electrolysis (e.g., with water), not molten.
• C: Reverses electrode products; magnesium is not oxidized at anode.
• D: Oxygen and hydrogen indicate aqueous solution electrolysis, not molten salt.

Final answer: A