Polyatomic ions

Definition

Polyatomic ions are charged particles composed of two or more covalently bonded atoms. They act as a single unit in chemical reactions and possess a net charge due to the loss or gain of electrons.

5 Must Know Facts For Your Next Test

1. Polyatomic ions can have either a positive or negative charge, though most are anions.
2. Common examples include sulfate ($SO_4^{2-}$), nitrate ($NO_3^-$), and ammonium ($NH_4^+$).
3. The charge of a polyatomic ion results from the total number of electrons being different from the total number of protons in the combined atoms.
4. Polyatomic ions often participate in both ionic and molecular compounds.
5. The name of many polyatomic anions ends with '-ate' or '-ite,' indicating different numbers of oxygen atoms.

Review Questions

Related terms

Monatomic Ion: An ion consisting of a single atom that has gained or lost one or more electrons, resulting in a net charge.

Covalent Bond:

A type of chemical bond where two atoms share one or more pairs of valence electrons.

Ionic Compound: A compound composed of positively and negatively charged ions held together by electrostatic forces.