Some Common Polyatomic Ions

Name of ion

Symbol

Name of ion

Symbol

Acetate

C2H3O2-

Hypobromite

BrO-

Ammonium

NH4+

Hypochlorite

ClO-

Arsenate

AsO43-

Hypoiodite

IO-

Borate

BO33-

Iodate

IO3-

Bromate

BrO3-

Iodide

I-

Bromide

Br-

Iodite

IO2-

Bromite

BrO2-

Nitrate

NO3-

Carbonate

CO32-

Nitride

N3-

Chlorate

ClO3-

Nitrite

NO2-

Chloride

Cl-

Oxalate

C2O42-

Chlorite

ClO2-

Oxide

O2-

Chromate

CrO42-

Perbromate

BrO4-

Cyanide

CN-

Perchlorate

ClO4-

Dichromate

Cr2O72-

Periodate

IO4-

Dihydrogen phosphate

H2PO4-

Permanganate

MnO4-

Fluoride

F-

Peroxide

O22-

Hydride

H-

Phosphate

PO43-

Hydrogen carbonate (bicarbonate)

HCO3-

Phosphite

PO33-

Hydrogen oxalate (bioxalate)

HC2O4-

Sulfate

SO42-

Hydrogen phosphate

HPO42-

Sulfide

S2-

Hydrogen sulfate (bisulfate)

HSO4-

Sulfite

SO32-

Hydrogen sulfide (bisulfide)

HS-

Thiosulfate

S2O32-

Hydrogen sulfite (bisulfite)

HSO3-

Hydroxide

OH-