Chemistry vocabulary · Atoms and the Periodic Table
Cation
Meaning in chemistry, with examples
/ˈkætaɪən/nounCommon term
In chemistry, cation means: An ion with a positive charge, formed when an atom or group of atoms loses electrons. Na⁺, Ca²⁺ and NH₄⁺ are examples.
In Turkish: katyon
How it is used
Used in inorganic, analytical and electrochemistry. Metals usually form cations, and in electrolysis cations move toward the cathode. In the name of a salt the cation comes first: sodium chloride.
Example sentences
Group 2 metals form cations with a 2+ charge.
The flame test identifies the metal cation in the salt.
Common collocations
metal cation
form a cation
cation exchange
monovalent cation
Related terms
anionAn ion with a negative charge, formed when an atom or group of atoms gains electrons. Cl⁻, OH⁻ and SO₄²⁻ are examples.
ionAn atom or group of atoms that carries an electric charge because it has gained or lost electrons. Positive ones are cations and negative ones are anions.
ionic bondThe strong attraction between positive and negative ions that forms when one atom, usually a metal, transfers electrons to another, usually a nonmetal. Sodium chloride is the classic case.
saltAn ionic compound made of positive and negative ions, usually formed when an acid reacts with a base. Sodium chloride is the best known, but there are thousands of others.
electronA tiny particle with a negative charge that moves around the nucleus of an atom. Chemical bonds and reactions are mostly about how these particles are shared or transferred.
