Question

Which of the following can be classified as an amphoteric oxide?

• A. Iron (III) oxide
• B. Aluminum (III) oxide
• C. Mercury (II) oxide
• D. Lime

Answer 1

The correct option is B Aluminum (III) oxide

Aluminium (III) oxide $\left(A{l}_2{O}_3\right)$ is an amphoteric oxide. Amphoteric oxides are those oxides which can act both as an acid as well as base.
$A{l}_2{O}_3+6HCl+9H_{2}O\to 2\left[Al\right(H_{2}O{)}_6{]}^{3+}+6C{l}^{-}A{l}_2{O}_3+6NaOH+3H_{2}O\to 2N{a}_3\left[Al\right(OH{)}_6]$