Q5 of 30 Page 56

What is the thermite reaction? How is it used to join the railway tracks or cracked machine parts?

Fe2O3(s) + 2Al(s) → 2Fe (l) + Al2O3(s) + Heat

The above reaction is known as the thermite reaction.


i. In this reaction, iron (III) oxide (Fe2O3) reacts with aluminium to form iron.


ii. This is a displacement reaction, and it is accompanied with a release of a large amount of energy.


iii. The energy released is so large that the iron so formed is in a molten state and thus it is used to join the railway tracks or cracked machine parts.


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