polyatomic ions

acetate

C₂H₃O₂^-

carbonate

CO₃^2-

hydrogen carbonate

HCO₃^-

hydroxide

OH^-

nitrite

NO₂^-

nitrate

NO₃^-

chromate

CrO₄^2-

dichromate

Cr₂O₇^2-

phosphate

PO₄^3-

hydrogen phosphate

HPO₄^2-

dihydrogen phosphate

H₂PO₄^-

ammonium

NH₄⁺

hypochlorite

ClO^-

chlorite

ClO₂^-

chlorate

ClO₃^-

perchlorate

ClO₄^-

permanganate

MnO₄^-

sulfite

SO₃^2-

hydrogen sulfite

HSO₃^-

sulfate

SO₄^2-

hydrogen sulfate

HSO₄^-

cyanide

CN

peroxide

O₂^2-