Polyatomic ion
A polyatomic ion is an ion (chemical compound with an electrical charge) that is made of multiple atoms. A polyatomic ion can be either a cation (positive charge) or anion (negative charge).
Many minerals contain polyatomic anions. Polyatomic cations are rarer, and are usually made by people.
| Cations | Anions | ||||
|---|---|---|---|---|---|
| Charge | Formula | Name | Charge | Formula | Name |
| +1 | H3O+ | Hydronium | -1 | OH− | Hydroxide |
| +1 | NH+4 | Ammonium | -1 | NO−3 | Nitrate |
| +2 | Hg2+2 | Mercury polycations | -1 | CH3COO− | Acetate |
| +2 | VO2+ | Vanadyl ion | -2 | SO2−4 | Sulfate |
| -2 | CO2−3 | Carbonate | |||
| -3 | C3H5O(COO)3−3 | Citrate | |||
| -3 | PO3−4 | Phosphate | |||
