Polyatomic ions have a systematic naming. The name must contain the participating Elements, ordered by the following rules:
- the electropositive Kation before the electonegative Anion, e.g. NaCL instead of ClNa, because Chlor is the partner to get the electron here.
- the parts are ordered by their element number, "lower" elements first.
- If the polyatomic ion consists of more than two elements, the ordering of the parts follows the structure in the molecule. SCN- instead of CNS-.
Here are some of the commonly used prefixes for naming of ions:
|Peroxo-||oxygen replaced by Peroxo O-O|
|Thio-||oxygen replaxed by Sulfur|