
Ion - Wikipedia
Ions consisting of only a single atom are termed monatomic ions, atomic ions or simple ions, while ions consisting of two or more atoms are termed polyatomic ions or molecular ions.
Ion | Definition, Chemistry, Examples, & Facts | Britannica
Nov 18, 2025 · Ion, any atom or group of atoms that bears one or more positive or negative electrical charges. Positively charged ions are called cations; negatively charged ions, anions. …
What Is an Ion? Definition and Examples - ThoughtCo
Sep 4, 2019 · Learn the definition of an ion, as used in chemistry, chemical engineering, and physics, plus review examples of ions.
Ion - Properties, Symbols and Formation | CK-12 Foundation
Dec 1, 2025 · Ions are atoms that have a positive or negative charge because they have unequal numbers of protons and electrons. If atoms lose electrons, they become positive ions, or cations.
What Is an Ion? Chemistry Definition - Science Notes and Projects
Nov 20, 2021 · In chemical reactions, ions form when atoms or molecules gain or lose valence electrons. Only nuclear reactions change the number of protons in a chemical species. The …
Ion Definition: Meaning, Types, Examples & Key Facts Explained
Atoms form ions to achieve a more stable electron configuration, typically that of the nearest noble gas. By losing or gaining electrons, an atom can attain a full outermost electron shell (an …
What Is An Ion In Chemistry? | The Science Blog
Jul 12, 2023 · What Is An Ion In Chemistry? An ion is an atom that has an electric charge because it’s either lost or gained one or more of its electrons. In chemistry, positively-charged …
ION Definition & Meaning - Merriam-Webster
The meaning of ION is an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons. How to use ion in a sentence.
Ions Explained: Definition, Examples, Practice & Video Lessons
Ions are atoms that have gained or lost electrons, resulting in a net electrical charge. When an atom loses electrons, it becomes a cation, which is a positively charged ion. Conversely, when …
11.4: Ions and Ion Formation - Chemistry LibreTexts
Ions are atoms that have a positive or negative charge because they have unequal numbers of protons and electrons. If atoms lose electrons, they become positive ions, or cations.