Question

$A{l}_2{O}_3$ can be reduced by carbon at a temperature of :

• A. ${30}^{\circ }C$
• B. ${500}^{\circ }C$
• C. ${1000}^{\circ }C$
• D. $>{2500}^{\circ }C$

Answer 1

The correct option is D $>{2500}^{\circ }C$

Explanation:
An Ellingham diagram is a graph showing the temperature dependence of the stability for compounds. This analysis is usually used to evaluate the ease of reduction of metal oxides and sulfides. These diagrams were first constructed by Harold Ellingham in $1944.$
Carbon cannot be used in the reduction of $A{l}_2{O}_3$ in metallurgy. Aluminum oxide is a very stable oxide and lies below the oxidation line of carbon in Ellingham Diagram. Hence, $A{l}_2{O}_3$ cannot be reduced by carbon as it is energetically not favorable.
A very high temperature is required. $A{l}_2{O}_3$ can be reduced by carbon at a temperature $>{2500}^{\circ }C$ as it is a stable oxide.