CBSE · Class 10 · Science · Metals and Non-metalsWhat is the Thermite Process? Write the chemical equation for the reaction involved. State one important practical application of this process and explain why it is highly exothermic.

Thermite Process Definition: The thermite process is a chemical reaction in which a metal oxide (usually Iron(III) oxide) is reduced by aluminium powder acting as a reducing agent. The reaction is so strongly exothermic that the reduced metal is produced in molten form.

Chemical Equation: $$\text{Fe}_2\text{O}_3\text{ (s)} + 2\text{Al (s)} \rightarrow 2\text{Fe (l)} + \text{Al}_2\text{O}_3\text{ (s)} + \text{Heat}$$

Practical Application: It is widely used for joining broken railway tracks, cracked machine parts, or heavy metallic structures on site.

Reason for Exothermic Nature: Aluminium has a much stronger chemical affinity for oxygen than iron does. During the reaction, the formation of extremely stable aluminium oxide ($\text{Al}_2\text{O}_3$) releases a tremendous amount of bond formation and lattice energy. The energy released raises the temperature of the system to over $2500^\circ\text{C}$, melting the iron produced immediately so that it can flow directly into metal gaps.