Chemistry - Metallurgy Question with Solution | TestHub

Question Explanation:

Identify the metal that cannot be extracted by the carbon reduction process.

Concept:

Carbon Reduction (Ellingham Diagram/Stability).

Solution:

Carbon reduction is ineffective for the oxides of highly electropositive metals, whose formation lines lie very low in the Ellingham diagram.

Pb (PbO), Sn (SnO₂), and Zn (ZnO) can all be reduced by carbon.

Aluminium (Al) oxide (Al₂O₃) is very stable, and Al is extracted by electrolytic reduction.