Common Polyatomic Ions

Ammonium

Ammonium

NH4+

Acetate

CH3COO-

Nitrate

NO3-

Nitrite

NO2-

Cyanide

CN-

Thiocyanate

SCN-

Hydrogen Carbonate

HCO3-

Hydrogen Sulfate

HSO4-

Hydrogen Sulfite

HSO3-

perchlorate

ClO4-

chlorate

ClO3-

chlorite

ClO2-

hypochlorite

ClO-

Iodate

IO3-

Bromate

BrO3-

Hydroxide

OH-

permanganate

MnO4-

thiosulfate

S2O3 -2

Sulfate

SO4 -2

sulfite

SO3 -2

Carbonate

CO3 -2

Dichromate

Cr2O7 -2

chromate

CrO4 -2

oxalate

C2O4 -2

silicate

SiO3 -2

Phosphate

PO4 -3

arsenate

AsO4 -3