polyatomic ions

NO3-

nitrate ion

NO2–

nitrite ion

SO42–

sulfate ion

SO32–

sulfite ion

CO32–

carbonate ion

ClO4–

perchlorate ion

ClO3–

chlorate ion

ClO2–

chlorite ion

ClO–

hypochlorite ion

CrO42–

chromate ion

Cr2O72-

dichromate ion

MnO4–

permanganate ion

OH –

hydroxide ion

CN–

cyanide ion

NH4+

ammonium ion

HSO4–

hydrogen sulfate ion

HCO3–

hydrogen carbonate ion

PO43–

phosphate ion

HPO42–

hydrogen phosphate ion

H2PO4–

dihydrogen phosphate ion

C2H3O2

acetate ion

C2O42–

oxalate ion

S2O32–

thiosulfate ion

SCN –

thiocyanate ion

NH4+

ammonium ion