Question

Group 13 elements are attacked by non-oxidising acids except:

• A. aluminium
• B. gallium
• C. indium
• D. boron

Answer 1

The correct option is D boron

Option $\left(D\right)$ is correct.

Boron is not attacked by non-oxidising acids such as $HCl$ but reacts with oxidising acids such as conc. $HN{O}_3$ and conc.$H_{2}S{O}_4$ forming boric acid.

Boron, being chemically a non-metal, is resistant to attack by non-oxidising acids but the other members of the group react with non-oxidising acids as typical metals and evolve hydrogen.