AP Chemistry Polyatomic Ion List

A comprehensive vocabulary review of common polyatomic ion names, chemical formulas, and charges for AP Chemistry.

Ammonium

Polyatomic ion with the formula and charge $NH_4^+$

Acetate

Polyatomic ion with the formula and charge $C_2H_3O_2^-$

Hydroxide

Polyatomic ion with the formula and charge $OH^-$

Cyanide

Polyatomic ion with the formula and charge $CN^-$

Chlorate

Polyatomic ion with the formula and charge $ClO_3^-$

Perchlorate

Polyatomic ion with the formula and charge $ClO_4^-$

Chlorite

Polyatomic ion with the formula and charge $ClO_2^-$

Hypochlorite

Polyatomic ion with the formula and charge $ClO^-$

Nitrate

Polyatomic ion with the formula and charge $NO_3^-$

Nitrite

Polyatomic ion with the formula and charge $NO_2^-$

Permanganate

Polyatomic ion with the formula and charge $MnO_4^-$

Carbonate

Polyatomic ion with the formula and charge $CO_3^{2-}$

Bicarbonate (Hydrogen Carbonate)

Polyatomic ion with the formula and charge $HCO_3^-$

Sulfate

Polyatomic ion with the formula and charge $SO_4^{2-}$

Hydrogen Sulfate

Polyatomic ion with the formula and charge $HSO_4^-$

Sulfite

Polyatomic ion with the formula and charge $SO_3^{2-}$

Hydrogen Sulfite

Polyatomic ion with the formula and charge $HSO_3^-$

Chromate

Polyatomic ion with the formula and charge $CrO_4^{2-}$

Dichromate

Polyatomic ion with the formula and charge $Cr_2O_7^{2-}$

Phosphate

Polyatomic ion with the formula and charge $PO_4^{3-}$

Hydrogen Phosphate

Polyatomic ion with the formula and charge $HPO_4^{2-}$

Dihydrogen Phosphate

Polyatomic ion with the formula and charge $H_2PO_4^-$