Question

The extraction of metals from oxide ores involve(s):

• A. Reduction with carbon
• B. Reduction with aluminium
• C. Electrolytic reduction
• D. Reduction with CO

Answer 1

Answer: (A), (B), (C), (D)

Reduction with CO

This is a question that tests several layers. For instance, both Carbon and Coke can be used during smelting where the metal oxide is reduced to the metal.
For extraction of iron using the blast furnace, coke is added and it is involved in the reduction process - although $CO$ is the principal reducing agent (above 710 ${}^{\circ }$).

In the thermite reduction process, powdered aluminium reduces metal oxides like $F{e}_2{O}_3$ and $C{r}_2{O}_3$ to their metal oxides at high temperatures. This redox reaction is highly exothermic and often the reduced metal is in the molten form.

In the Hall-Heroult process, alumina $A{l}_2{O}_3$ is reduced electrolytically to molten aluminium.