Question

Classify the ions listed below as monatomic or polyatomic cations or anions. If the ion is a polyatomic anion, indicate whether it is an oxyanion.

a. CN⁻
b. MnO⁻4
c. Ba²⁺
d. Fe(CN)₆⁴⁻
e. NH₄⁺
f. N³⁻
g. Hg₂²⁺
h. S₂O₃²⁻
I. O²⁻

Answer 1

The ammonium ion (NH₄⁺) is a polyatomic cation, while the oxide ion (O²⁻) is a monatomic anion, which is not an oxyanion.

Step-by-step explanation:

The NH₄⁺ ion, commonly referred to as the ammonium ion, is a polyatomic cation composed of four hydrogen atoms and one nitrogen atom. This molecular arrangement imparts a positive charge to the ion. In contrast, the O²⁻ ion, known as the oxide ion, is a monatomic anion consisting solely of one oxygen atom carrying a negative charge. The distinction lies in their atomic structures:

NH₄⁺ is a complex, multi-atomic cation, while O²⁻ is a simple, single-atom anion. Notably, the oxide ion is not classified as an oxyanion because it lacks oxygen in a polyatomic configuration. This differentiation in atomic composition and charge underscores the diversity of ions and their roles in various chemical reactions.