Polyatomic ions

Hg_2

Mercury I(2+)

NH_4

Ammonium(+)

NO_2

Nitrite(-)

NO3

Nitrate(-)

SO_3

Sulfite(-2)

SO_4

Sulfate(2-)

HSO_4

Hydrogen Sulfate (bisulfate)(-)

OH

Hydroxide(-)

CN

Cyanide-

PO_4

Phosphate(3-)

HPO_4

Hydrogen phosphate(2-)

H_2PO_4

Dihydrogen phosphate(-)

NCS or SCN

Thiocyanate-

CO_3

Carbonate(2-)

HCO_3

Hydrogen carbonate (bicarbonate)(-)

CIO or OCl-

Hypochlorite-

CIO_2

Chlorite(-)

ClO_3

Chlorate(-)

ClO_4

Perchlorate(-)

C_2H_3O_2

Acetate(-)

MnO_4

Permanganate(-)

Cr_2O_7

Dichromate(2-)

CrO_4

Chromate(2-)

O_2

Peroxide(2-)

C_2O_4

Oxalate(2-)

S_2O_3

Thiosulfate(2-)