Q2 of 805 Page 169

Which of the following are physical changes?

(i) Melting of iron metal


(ii) Rusting of iron


(iii) Bending of an iron rod


(iv) Drawing a wire of iron metal

Rusting is a chemical change where iron and oxygen react together to make a new substance of completely different properties called iron oxide.


The chemical reaction is given as:


4Fe + 3O2 → 2Fe2O3


Rest all are physical changes.

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