Question

Find the odd one out (valency is not a criterion).

• A. $\mathrm{Al}{\left(\mathrm{OH}\right)}_3$
• B. $\mathrm{Pb}{\left(\mathrm{OH}\right)}_2$
• C. $\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$
• D. $\mathrm{Zn}{\left(\mathrm{OH}\right)}_2$

Answer 1

The correct option is C

$\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$

Among the given option $\mathrm{c})\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$ is the odd one.

Reason for Correct answer-

1. Generally, the metallic hydroxides are basic in nature.
2. Magnesium hydroxide $\mathrm{c})\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$ is a basic compound.
3. It is also called Milk of Magnesia or Magnesium hydroxide.

Reason for Incorrect answer -

1. All other given compounds are amphoteric hydroxides.
2. An amphoteric substance can act as an acid and as well as a base.

Hence, option c is correct.