Which of the following metals is NOT extracted by electrolysis?

1. Analyze the question You are asked which metal is NOT extracted by electrolysis. Extraction method depends on the metal's position in the reactivity series.

2. Explain the concept

• Highly reactive metals (K, Na, Ca, Mg, Al) hold on to oxygen or chlorine very strongly. Carbon cannot reduce their ores, so they are extracted by electrolysis of the molten compound.
• Moderately reactive metals (Zn, Fe, Pb) are extracted by chemical reduction with carbon or carbon monoxide.
• Unreactive metals (Cu, Ag, Au) are found native or are easily reduced.

3. Apply it to each option

• A. Aluminium: electrolysis of molten alumina (Al₂O₃) dissolved in cryolite (Hall-Héroult process).
• B. Calcium: electrolysis of molten calcium chloride.
• C. Iron: extracted in the blast furnace. Haematite (Fe₂O₃) is reduced by carbon monoxide: Fe₂O₃ + 3CO → 2Fe + 3CO₂ No electrolysis is involved.
• D. Magnesium: electrolysis of molten magnesium chloride.
• E. Sodium: electrolysis of molten sodium chloride (Downs cell).

4. Answer Iron is the only metal in the list extracted by chemical reduction rather than electrolysis.

Correct option: C

Exam tip: Remember that metals above carbon in the reactivity series (K, Na, Ca, Mg, Al) are extracted by electrolysis, while those below carbon (Zn, Fe, Pb, Cu) are extracted by reduction with carbon. A simple memory line: "If it is above carbon, use electrolysis."