Question

dinitrogen monoxide - no₂
sulfur trioxide - so₃
phosphorus pentachloride - pcl₅
select all polyatomic ions from the list below.
cl⁻
no₃⁻
so₄²⁻
mg²⁺

Explanation:

A polyatomic ion is a charged species composed of two or more atoms covalently bonded.

• $\text{Cl}^-$: Monoatomic ion (1 atom).
• $\text{NO}_3^-$: Polyatomic (N + 3 O, charged).
• $\text{SO}_4^{2-}$: Polyatomic (S + 4 O, charged).
• $\text{Mg}^{2+}$: Monoatomic ion (1 atom).

So $\text{NO}_3^-$ and $\text{SO}_4^{2-}$ are polyatomic ions.

Answer:

B. $\text{NO}_3^-$, C. $\text{SO}_4^{2-}$