Appendix E: Polyatomic Ions
Common Polyatomic Ions
| Name | Symbol |
|---|---|
| Acetate | C2H3O2– |
| Amide | NH2– |
| Ammonium | NH4+ |
| Arsenate | AsO43- |
| Borate | BO33- |
| Bromate | BrO3– |
| Carbonate | CO32- |
| Chlorate | CIO3– |
| Chlorite | CIO2– |
| Chromate | CrO42- |
| Cyanide | CN– |
| Dichromate | CrO72- |
| Dihydrogen phosphate | H2PO42- |
| Hydrogen carbonate | HCO3– |
| Hydrogen oxalate | HC2O4– |
| Hydrogen phosphate | HPO42- |
| Hydrogen sulfate (bisulfate) | HSO4– |
| Hydrogen sulfite (bisulfate) | HSO3– |
| Hydroxide | OH– |
| Hypobromite | BrO– |
| Hypochlorite | CIO– |
| Hypoiodite | IO– |
| Iodate | IO3– |
| Nitrate | NO3– |
| Nitrite | NO2– |
| Oxalate | C2O42- |
| Perchlorate | CIO4– |
| Periodate | IO4– |
| Permanganate | MnO4– |
| Peroxide | O22- |
| Phosphate | PO43- |
| Phosphite | PO33- |
| Sulfate | SO42- |
| Sulfite | SO32- |
| Thiocyanide | SCN– |
Attribution & References
Except where otherwise noted, this page is adapted by Samantha Sullivan Sauer from “Chapter 3: Ions and Ionic Compounds & Molecules and Chemical Nomenclature” In Introductory Chemistry: 1st Canadian Edition by David W. Ball and Jessica A. Key, licensed under CC BY-NC-SA 4.0.