Common Polyatomic Ions

acetate

CH3O2−

ammonium

NH4+

arsenate

AsO4^{3-}

azide

N3−

benozoate

C7H5O2−

borate

BO3^{3-}

bromate

BrO3−

carbonate

CO3^{2-}

chlorate

ClO3−

chlorite

ClO2−

chromate

CrO4^{2-}

cynanide

CN−

dichromate

Cr2O7^{2-}

dihydrogen phosphate

H2PO4−

dihydrogen phosphite

H2PO3−

hydrogen carbonate

HCO3−

hydrogen phosphate

HPO4²−

hydrogen phopsphite

HPO3²−

hydrogen sulfate

HSO4-

hydrogen sulfide

HS-

hydrogen sulfite

HSO3-

hydroxide

OH-

hypochlorite

CIO-

iodate

IO3-

maganate

MnO4²-

nitrate

NO3-

nitrite

NO2-

oxalate

C2O4²-

perchlorate

CIO4-

permanganate

MnO4-

peroxide

O2²-

phosphate

PO4³-

silicate

SiO3²-

sulfate

SO4²-

sulfite

SO3²-

tartrate

C4H4O6²-

thiocyanate

SCN-

thiosulfate

S2O3²-