Polyatomic Ions

ammonium

NH4(+)

nitrite

NO2(-)

nitrate

NO3(-)

sulfite

SO3(2-)

sulfate

SO4(2-)

hydroxide

OH(-)

cyanide

CN(-)

phosphate

PO4(3-)

carbonate

CO3(2-)

hydrogen carbonate

HCO3(-)

hypochlorite

ClO(-)

chlorite

ClO2(-)

chlorate

ClO3(-)

perchlorate

ClO4(-)

acetate

C2H3O2(-) or CH3COO(-)

permanganate

MnO4(-)

dichromate

Cr2O7(2-)

chromate

CrO4(2-)

peroxide

O2(2-)

bromate

BrO3 (-)

thiocyanate

SCN(-)

oxalate

C2O4 (2-)

arsenate

AsO4(3-)

iodate

IO3(-)

phosphite

PO3(3-)