Common Polyatomic Ions

OH^-

Hydroxide

CN^-

Cyanide

SCN^-

Thiocyanate

HCO₃^-

Hydrogen Carbonate

HSO₃^-

Hydrogen Sulfite

HSO₄^-

Hydrogen Sulfate

C₂H₃O₂^-

Acetate

NO₂^-

Nitrite

NO₃^-

Nitrate

MnO₄^-

Permanganate

CLO^-

Hypochlorite

CLO₂^-

Chlorite

ClO₃^-

Chlorate

ClO₄^-

Perchlorate

O₂^2-

Peroxide

CO₃^2-

Carbonate

SO₃^2-

Sulfite

SO₄^2-

Sulfate

S₂O₃^2-

Thiosulfate

C₂O₄^2-

Oxalate

CrO₄^2-

Chromate

Cr₂O₇^2-

Dichromate

PO₃^3-

Phosphite

PO₄^3-

Phosphate

NH₄⁺

Ammonium

Hg₂²⁺

Mercury (I)