Question

Which amongst the following does not represent a polyatomic ion?

• A. Carbonate
• B. Chloride
• C. Sulphate
• D. Phosphate

Answer 1

The correct option is B

Chloride

A polyatomic ion is an ion that is composed of more than two atoms.
$$\begin{array}{cc}\text{Ion}& \text{Formula}\\ \text{Carbonate}& C{O}_3^{2-}\\ \text{Chloride}& C{l}^{-}\\ \text{Sulphate}& S{O}_4^{2-}\\ \text{Phosphate}& P{O}_4^{3-}\end{array}$$

Here, carbonate, sulphate and phosphate ions are polyatomic as they contain more than one atom. While chloride is a monoatomic ion.