Polyatomic Ions

ammonium

NH4 +

hydronium

H3O +

peroxide

O2 2-

hydroxide

OH –

acetate

C2H3O2 -

cyanide

CN–

azide

N3 -

chromate

CrO4 2–

dichromate

Cr2O7 2–

permanganate

MnO4 –

carbonate

CO3 2-

hydrogen carbonate

HCO3 –

nitrate

NO3 -

nitrite

NO2 –

sulfate

SO4 2–

sulfite

SO3 2–

hydrogen sulfate

HSO4 –

hydrogen sulfite

HSO3 –

phosphate

PO4 3–

hydrogen phosphate

HPO4 2–

dihydrogen phosphate

H2PO4 –

perchlorate

ClO4 –

chlorate

ClO3 –

chlorite

ClO2 –

hypochlorite

ClO –