Question

A popular metal X reacts with oxygen gas to give an amphoteric oxide. Identify the metal X. Recall that amphoteric oxides show both acidic and basic behaviour.
$X+O_2\to \text{Amphoteric Oxide}$

• A. Na (Sodium)
• B. Al (Aluminium)
• C. C (Carbon)
• D. K (Potassium)

Answer 1

The correct option is B

Al (Aluminium)

Metal oxides which react with both acids as well as bases to produce salts and water are known as amphoteric oxides.

Aluminium on reaction with oxygen forms $A{l}_2{O}_3$. This metal oxide shows both acidic as well as basic behavior.
$\text{Reaction of}A{l}_2{O}_3\text{with acid}A{l}_2{O}_3\left(s\right)+6HCl\left(aq\right)\to 2AlC{l}_3+3H_{2}O\text{Rection of}A{l}_2{O}_3\text{with base}A{l}_2{O}_3\left(s\right)+2NaOH\left(aq\right)\to 2NaAl{O}_2\left(aq\right)+H_{2}O\left(l\right)$