Question

Which metal is extracted by electrolytic reduction?

• A. Zinc
• B. Iron
• C. Sodium
• D. Copper

Hint:

Highly reactive metals (high in the reactivity series) are extracted by electrolytic reduction of their molten salts, while moderately reactive metals can be extracted using reducing agents like carbon.

Answer 1

The Correct Option is C

Step 1: Metals high in the reactivity series (like sodium, potassium, calcium, etc.) cannot be extracted using conventional chemical reduction methods (e.g., using carbon or carbon monoxide).
Step 2: These highly reactive metals are extracted by electrolytic reduction, where their molten salts (like molten NaCl) are electrolyzed.
Step 3: In the case of sodium, molten sodium chloride is electrolyzed to produce sodium metal at the cathode: \[ \text{Na}^+ + e^- \rightarrow \text{Na (at cathode)} \] Step 4: Metals like zinc and iron can be extracted by reduction with carbon, while copper is usually extracted from its ore by roasting and refining. Hence, only sodium is extracted using electrolytic reduction.