Some Common Polyatomic Ions


Cations

+1

+2

NH4+ Ammonium

Hg22+ Mercury (I) or Mercurous

Anions

-1

-2

-3

-4

C2H3O2- Acetate

CO32- Carbonate

AsO43- Arsenate

Fe(CN)64- Hexacyanoferrate (II) or Ferrocyanide

AlO2- Aluminate

CrO42- Chromate

AsO33- Arsenite


HCO3- Bicarbonate, Hydrogen Carbonate

Cr2O72- Dichromate

Fe(CN)63- Hexacyanoferrate (III) or Ferricyanide


BrO3- Bromate

C2O42- Oxalate

PO43- Phosphate


ClO4- Perchlorate

O22- Peroxide

PO33- Phosphite


ClO3- Chlorate

SiO32-Silicate



ClO2- Chlorite


SO42- Sulfate



ClO- Hypochlorite

SO32- Sulfite



CrO2- Chromite

C4H4O62- Tartrate



CN- Cyanide

S2O32- Thiosulfate



OH- Hydroxide

MoO42-Molybdate



IO3- Iodate.




NO3- Nitrate




NO2- Nitrite




MnO4- Permanganate




Consult your periodic table for a more complete list of oxidation states of other monoatomic ions