Polyatomic Ions Study Sheet

A set of vocabulary flashcards detailing common polyatomic ions, their chemical formulas, ionic charges, and key structural patterns.

Ammonium

A polyatomic cation with the formula $NH_4^+$ and a charge of $+1$.

Nitrite

A polyatomic anion with the formula $NO_2^-$ and a charge of $-1$.

Nitrate

A polyatomic anion with the formula $NO_3^-$ and a charge of $-1$.

Sulfite

A polyatomic anion with the formula $SO_3^{2-}$ and a charge of $-2$.

Sulfate

A polyatomic anion with the formula $SO_4^{2-}$ and a charge of $-2$.

Hydrogen sulfate (bisulfate)

A polyatomic anion with the formula $HSO_4^-$ and a charge of $-1$.

Hydrogen sulfite (bisulfite)

A polyatomic anion with the formula $HSO_3^-$ and a charge of $-1$.

Hydroxide

A polyatomic anion with the formula $OH^-$ and a charge of $-1$.

Cyanide

A polyatomic anion with the formula $CN^-$ and a charge of $-1$.

Phosphate

A polyatomic anion with the formula $PO_4^{3-}$ and a charge of $-3$.

Hydrogen phosphate

A polyatomic anion with the formula $HPO_4^{2-}$ and a charge of $-2$.

Dihydrogen phosphate

A polyatomic anion with the formula $H_2PO_4^-$ and a charge of $-1$.

Carbonate

A polyatomic anion with the formula $CO_3^{2-}$ and a charge of $-2$.

Hydrogen carbonate (bicarbonate)

A polyatomic anion with the formula $HCO_3^-$ and a charge of $-1$.

Hypochlorite

A polyatomic anion with the formula $ClO^-$ and a charge of $-1$.

Chlorite

A polyatomic anion with the formula $ClO_2^-$ and a charge of $-1$.

Chlorate

A polyatomic anion with the formula $ClO_3^-$ and a charge of $-1$.

Perchlorate

A polyatomic anion with the formula $ClO_4^-$ and a charge of $-1$.

Acetate

A polyatomic anion with the formula $C_2H_3O_2^-$ and a charge of $-1$.

Permanganate

A polyatomic anion with the formula $MnO_4^-$ and a charge of $-1$.

Mercury(I)

A special paired polyatomic cation with the formula $Hg_2^{2+}$ and a charge of $+2$.

Mercury(II)

A cation with the formula $Hg^{2+}$ and a charge of $+2$.

Chromate

A polyatomic anion with the formula $CrO_4^{2-}$ and a charge of $-2$.

Dichromate

A polyatomic anion with the formula $Cr_2O_7^{2-}$ and a charge of $-2$.

Peroxide

A polyatomic anion with the formula $O_2^{2-}$ and a charge of $-2$.

Superoxide

A polyatomic anion with the formula $O_2^-$ and a charge of $-1$.

Oxalate

A polyatomic anion with the formula $C_2O_4^{2-}$ and a charge of $-2$.

Hydrogen oxalate

A polyatomic anion with the formula $HC_2O_4^-$ and a charge of $-1$.

Formate

A polyatomic anion with the formula $CHO_2^-$ and a charge of $-1$.

Thiosulfate

A polyatomic anion with the formula $S_2O_3^{2-}$ and a charge of $-2$.

Hydrogen thiosulfate

A polyatomic anion with the formula $HS_2O_3^-$ and a charge of $-1$.

Perbromate

A polyatomic anion with the formula $BrO_4^-$ and a charge of $-1$.

Bromate

A polyatomic anion with the formula $BrO_3^-$ and a charge of $-1$.

Bromite

A polyatomic anion with the formula $BrO_2^-$ and a charge of $-1$.

Hypobromite

A polyatomic anion with the formula $BrO^-$ and a charge of $-1$.

Periodate

A polyatomic anion with the formula $IO_4^-$ and a charge of $-1$.

Iodate

A polyatomic anion with the formula $IO_3^-$ and a charge of $-1$.

Iodite

A polyatomic anion with the formula $IO_2^-$ and a charge of $-1$.

Hypoiodate

A polyatomic anion with the formula $IO^-$ and a charge of $-1$.

Halogen Oxyanion Oxygen Trend

The structural pattern for halogen oxyanions progressing from hypo…ite to …ite to …ate to per…ate corresponding to $1$ to $2$ to $3$ to $4$ oxygen atoms.