Question

A. Fill in the blank spaces by choosing the correct words from the given list.

List : Suphurous, nitric acid, slowly, oxygen, phosphoric

4. Rusting takes place ___________.

Answer 1

• Rusting: The slow conversion of iron into its hydrated ferric oxide, in the presence of moisture and air, is called rusting, and the hydrated oxide of iron is called rust. The given reaction is
• $\underset{\mathrm{Iron}}{4\mathrm{Fe}\left(\mathrm{s}\right)}+\underset{\mathrm{Oxygen}}{3{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Ferric}\mathrm{oxide}}{2{\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)}$
• $\underset{\mathrm{Ferric}\mathrm{oxide}}{{\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{xH}}_2\mathrm{O}}\left(\mathrm{l}\right)\to \underset{\mathrm{Hydrated}\mathrm{ferric}\mathrm{oxide}}{{\mathrm{Fe}}_2{\mathrm{O}}_3.{\mathrm{xH}}_2\mathrm{O}\left(\mathrm{s}\right)}\left(\mathrm{rust}\right)$
• This is not an instantaneous reaction; rather, it occurs over a long period of time. When oxygen atoms react with iron atoms, iron oxides are formed. As a result, the bonds between iron atoms in the object/structure are weakened.

Therefore, rusting takes place slowly