polyatomic ions

NH3

NH3

ammonia

NH4 +

ammonium

ClO -

hypochlorite

ClO2 -

chlorite

ClO3 -

chlorate

ClO4 -

perchlorate

O2 2-

peroxide

C2H3O2 -

acetate

CN -

cyanide

CNO -

cyanate

SCN -

thiocyanate

SO3 2-

sulfite

SO4 2-

sulfate

S2O4 2-

thiosulfate

HSO4 -

bisulfate

CO3 2-

carbonate

HCO3 -

bicarbonate

NO2 -

nitrite

NO3 -

nitrate

PO3 3-

phosphite

PO4 3-

phosphate

HPO4 2-

hydrogen phosphate

H2PO4 -

dihydrogen phosphate

CrO4 2-

chromate

Cr2O7 2-

dichromate

C2O4 2-

oxalate

OH -

hydroxide

Hg2 2+

mercury (I) ion

H3O +

hydronium

MnO4 -

permanganate ion