Polyatomic Ions

acetate	C₂H₃O₂^1-
ammonium	NH₄¹⁺
arsenate	AsO₄^3-
azide	N₃^1-
bicarbonate (hydrogen carbonate)	HCO₃^1-
bisulfate (hydrogen sulfate)	HSO₄^1-
borate	BO₃^3-
bromate	BrO₃^1-
carbonate	CO₃^2-
chlorate	ClO₃^1-
chromate	CrO₄^2-
cyanate	OCN^1-
cyanide	CN^1-
dichromate	Cr₂O₇^2-
dihydrogen phosphate	H2PO4^1-
ferricyanide	Fe(CN)₆^3-
ferrocyanide	Fe(CN)₆^4-
formate	CHO₂^1-
hydrogen carbonate (bicarbonate)	HCO₃^1-
hydrogen sulfate(bisulfate)	HSO₄^1-
hydroxide	OH^1-
iodate	IO₃^1-
manganate**	MnO₄^2-
metasilicate	SiO₃^2-
molybdate	MoO₄^2-
monohydrogen phosphate	HPO₄^2-
nitrate	NO₃^1-
oxalate	C₂O₄^2-
permanganate**	MnO₄^1-
phosphate	PO₄^3-
phthalate	C₈H₄O₄^2-
selenate	SeO₄^2-
silicate	SiO₄^4-
sulfate	SO₄^2-
tartrate	C₄H₄O₆^2-
thiocyanate	SCN^1-
thiosulfate	S₂O₃^2-
tungstate	WO₄^2-

         ** Exception to prefix rules

NOTE: -ite ending means one less oxygen than the -ate form.

PREFIXES:
per- = one more oxygen than -ate
hypo- = one less oxygen than -ite