Common Polyatomic Molecules

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Ammonium

NH₄⁺

Hydronium

H₃O⁺

Peroxide

O₂^2-

Hydroxide

OH^-

Acetate

CH₃COO^-

Cyanide

CN^-

Azide

N₃^-

Carbonate

CO₃^2-

Bicarbonate

HCO₃^-

Nitrate

NO₃^-

Nitrite

NO₂^-

Sulfate

SO₄^2-

Hydrogen Sulfate

HSO₄^-

Sulfite

SO₃^2-

Hydrogen Sulfite

HSO₃^-

Phosphate

PO₄^3-

Hydrogen Phosphate

HPO₄^2-

Dihydrogen Phosphate

H₂PO₄^-

Perchlorate

ClO₄^-

Chlorate

ClO₃^-

Chlorite

ClO₂^-

Hypochlorite

ClO^-

Chromate

CrO₄^2-

Dichromate

Cr₂O₇^2-

Permanganate

MnO₄^-

Phosphite

PO₃^3-

Perbromate

BrO₄^-

Bromate

BrO₃^-

Bromite

BrO₂^-

Hypobromite

BrO^-