Common Polyatomic Ions

Ammonium Ion

NH??, cation

Acetate Ion

C?H?O?

Carbonate Ion

CO?

Hydrogen carbonate ion

HCO?

Hypochlorite Ion

ClO

Chlorite Ion

ClO?

Chlorate Ion

ClO?

Perchlorate Ion

ClO?

Chromate Ion

CrO?

Dichromate Ion

Cr?O?

Cyanate Ion

OCN

Thiocyanate Ion

SCN

Cyanide Ion

CN

Hydroxide Ion

OH

Nitrite Ion

NO?

Nitrate Ion

NO?

Oxalate Ion

C?O?

Permanganate Ion

MnO?

Phosphate Ion

PO?

Hydrogen phosphate ion

HPO?

Dihydrogen phosphate ion

H?PO?

Sulfite ion

SO?

Hydrogen Sulfite ion

HSO?

Sulfate ion

SO?

hydrogen sulfate ion

HSO?

thiosulfate ion

S?O?