Summary:
- A polyatomic ion is an ion composed of more than one atom.
- Some of the most useful materials we work with contain polyatomic ions.
- Many materials exist as simple binary compounds composed of a metal cation and a non-metal anion, with each ion consisting of only one type of atom.
- Other combinations of atoms also exist, either larger ionic complexes or complete molecules.
- The atoms of a polyatomic Ion are tightly bonded together and so the entire ion behaves as a single unit.