Question

Assertion (A): Aluminium is used as a reducing agent in aluminothermy.

Reason (R): Aluminium has a lower melting point than Fe, Cr and Mn.

Options

• If both A and R are true, and R is the correct explanation of A.

• If both A and R are true, but R is not the correct explanation of A.

• If A is true, but R is false.

• If both A and R are false.

Answer 1

If both A and R are true, but R is not the correct explanation of A.

Explanation:

The assertion is true because aluminium has a very high affinity for oxygen, making it an excellent reducing agent in aluminothermy (Goldschmidt process) to extract metals like iron, chromium, and manganese from their oxides. The reason is also true because aluminium has a lower melting point (around 660°C) than Fe, Cr, and Mn, all of which melt above 1200°C. However, R is not the correct explanation for A because aluminium's reducing power is entirely due to its strong thermodynamic tendency to form stable aluminium oxide (Al₂O₃) by releasing an immense amount of heat, not because of its melting point.