Monatomic ions

Definition

Monatomic ions are single atoms that have gained or lost electrons, resulting in a net electrical charge. They can be either positively charged (cations) or negatively charged (anions).

5 Must Know Facts For Your Next Test

1. Monatomic cations are typically formed by metal atoms losing one or more electrons.
2. Monatomic anions are usually formed by nonmetal atoms gaining one or more electrons.
3. The charge of a monatomic ion is indicated by a superscript number and sign after the element symbol, such as Na^+ or Cl^-.
4. Transition metals often form monatomic ions with multiple possible charges, like Fe^2+ and Fe^3+.
5. The stability of monatomic ions is influenced by the ionization energy for cations and electron affinity for anions.

Review Questions

• What distinguishes a monatomic ion from other types of ions?
• How are monatomic cations and anions typically formed?
• Give an example of a transition metal that can form more than one type of monatomic ion.

Related terms

Cation:

A positively charged ion formed when an atom loses one or more electrons.

Anion: A negatively charged ion formed when an atom gains one or more electrons.

Polyatomic Ion:

An ion composed of two or more atoms covalently bonded, carrying a net charge.