Cation and anion: differences and characteristics (with examples)

A cation is an ion that has a positive charge and an anion is an ion with a negative charge. Both cations and anions are types of ions. An ion is an atom or group of atoms that have an electric charge, i.e., they have a difference between the number of protons and the number of electrons that make up the ion.

Difference	Cations	Anions
Definition	Positively charged ion	Negatively charged ion
Formation	Formed by loss of electrons	Formed by electron gain
Charge	Positive charge	Negative charge
Types of ions	Mono-atomic cations Poly-atomic cations Mono-valent cations Divalent cations Trivalent cations	Mono-atomic anions Poly-atomic anions Mono-valent anions Divalent anions Trivalent anions
Examples	Sodium ion: Na⁺ Potassium ion: K⁺ Calcium ion: Ca²⁺ Silver ion: Ag⁺ ammonium ion: NH₄⁺	Chloride ion: Cl^– Oxygen ion: O^2- Sulfide ion: S^2- Sulfate ion: SO₄^2- Hydroxyl ion: OH^–

What is an anion

An anion in chemistry is defined as an ion that is negatively charged because it has excess electrons. An anion is formed when it gains electrons, i.e., it gains one or more negative charges.

Examples of common anions

We present you a list of the different types of anions.

Monoatomic monovalent anions: ions of a single atom with a negative charge.

Chloride anion Cl^–
Fluoride anion F^–
Bromide anion Br^–
Iodide I anion^–
Hydride anion H^–

Divalent monoatomic anions: ions of a single atom with two negative charges.

Sulfide anion S^2-
Oxide anion O^2-

Trivalent monoatomic anions: ions of a single atom with three negative charges.

Nitride anion N^3-
Phosphide anion P^3-
Arsenide anion As^3-

Polyatomic anions: ions of two or more atoms.

What is a cation

A cation in chemistry is defined as an ion that is positively charged because it lost electrons from its outermost shell. Cations are formed when they lose one or more electrons from their valence shell.