Question

What are amphoteric oxides?

Answer 1

Amphoteric oxides

• Amphoteric molecules are those substances that act as acids as well as bases. It depicts that these molecules are able to donate and accept ${\mathrm{H}}^{+}$ ions.

Example of amphoteric oxides

• Aluminum oxide$\left({\mathrm{Al}}_2{\mathrm{O}}_3\right)$ reacts in the following manner with acids and bases as follows:-
• The reaction of Aluminum oxide with acid that is hydrochloric acid $\left(\mathrm{HCl}\right)$ is as follows:-

$$\begin{gathered} {\mathrm{Al}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+6\mathrm{HCl}\left(\mathrm{aq}\right)\to 2{\mathrm{AlCl}}_3\left(\mathrm{aq}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Aluminum}\mathrm{oxide}\mathrm{Hydrogen}\mathrm{chloride}\mathrm{Aluminum}\mathrm{chloride}\mathrm{Water} \end{gathered}$$

• The reaction of Aluminum oxide with the base that is sodium hydroxide $\left(\text{NaOH}\right)$ is as follows:-

$$\begin{gathered} {\mathrm{Al}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+2\mathrm{NaOH}\left(\mathrm{aq}\right)\to 2{\mathrm{NaAlO}}_2\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Aluminum}\mathrm{oxide}\mathrm{Sodium}\mathrm{hydroxide}\mathrm{Sodium}\mathrm{aluminate}\mathrm{Water} \end{gathered}$$