Question

If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust. (a) Do you think rust is different from iron?

Answer 1

Rust:

• When iron reacts with water and atmospheric oxygen a reddish-brown layer of hydrated iron oxide is formed which is called rust.
• The balanced chemical reaction of the formation of rust can be represented as:
• $\underset{\mathrm{Iron}}{4\mathrm{Fe}\left(\mathrm{s}\right)}+\underset{\mathrm{Oxygen}}{3{\mathrm{O}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Moisture}}{{\mathrm{xH}}_2\mathrm{O}\left(\mathrm{g}\right)}\to \underset{\mathrm{Ferric}\mathrm{Hydroxide}}{2{\mathrm{Fe}}_2{\mathrm{O}}_3.{\mathrm{xH}}_2\mathrm{O}\left(\mathrm{s}\right)}$

Hence, Rust is different from iron, Rust is a reddish-brown substance of Iron (III) oxide. ,