Question

What is polyatomic ions?

Answer 1

Answer:

An ion is polyatomic if it contains more than one atoms.

Explanation:

The prefix "poly-" in the word polyatomic means "more than one." A polyatomic ion contains more than one atoms. Note that these atoms might belong to the same element. For example, in the book Foundations of Introductory College Chemistry, the triiodide ion $\rm {I_3}^{-}$ (note the subscript) is also classified as "polyatomic."

Other (more common) examples include:

• the sulfate ion, $\rm {SO_4}^{2-}$, which contains five atoms, and
• the hydroxide ion, $\rm OH^{-}$, which contains two atoms.

In contrast, an ion is monatomic (with the prefix "mono-") if it contains only one atom. Examples include:

• the chloride ion, $\rm Cl^{-}$,
• the iodide ion, $\rm I^{-}$ (without the subscript,) and
• the sodium ion, $\rm Na^{+}$