Question

Hydrated ferric oxide is called _________ .

Answer 1

Rust - It is the reddish-brown colored powder that is formed by rusting of iron.

Rusting - The reaction of iron (Fe) with oxygen (O₂) and moisture (H₂O) in the air resulting in the formation of reddish-brown colored hydrated iron oxide(rust) is called rusting.

$\underset{\mathrm{Iron}}{4\mathrm{Fe}\left(\mathrm{s}\right)}+\underset{\mathrm{Oxygen}}{3{\mathrm{O}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{{\mathrm{xH}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Hydrated}\mathrm{ferric}\mathrm{oxide}\left(\mathrm{Rust}\right)}{2{\mathrm{Fe}}_2{\mathrm{O}}_3.{\mathrm{xH}}_2\mathrm{O}\left(\mathrm{s}\right)}$

Necessary conditions for rusting-

• Presence of oxygen(air).
• Presence of water in either liquid or gaseous form.

Therefore, the hydrated ferric oxide is called rust.