Question

What is the chemical name of rust? Write its formula.

Answer 1

Rust

• If you leave a piece of iron in the open for some time, it acquires a film of brownish substance. This substance is called rust.
• This process is called rusting.
• The chemical name of rust is Iron(III) oxide or Ferric oxide.
• The formula for rust is ${\mathrm{Fe}}_2{\mathrm{O}}_3·x{\mathrm{H}}_2\mathrm{O}$.

Process of rusting

• For rusting, the presence of both water (or water vapor) and oxygen are essential.
• The process of rusting can be represented by the equation given below:-

$$\begin{gathered} 4\mathrm{Fe}\left(\mathrm{s}\right)+3{\mathrm{O}}_2\left(\mathrm{g}\right)+x\mathit{·}{\mathrm{H}}_2\mathrm{O}\to 2{\mathrm{Fe}}_2{\mathrm{O}}_3·x{\mathrm{H}}_2\mathrm{O}\left(\mathrm{s}\right) \\ \mathrm{Iron}\mathrm{oxygen}\mathrm{Hydrated}\mathrm{Iron}\left(\mathrm{III}\right)\mathrm{oxide} \end{gathered}$$