Polyatomic ions

Ammonium

NH₄ +

Acetate

(C₂H₃O₂) -1

Nitrate

(NO₃) -1

Bromate

(BrO₃) -1

  Nitrite

(NO₂) -1

Perchlorate

(ClO₄) -1

Cyanide

(CN) -1

Chlorate

(ClO₃) -1

Hydroxide

(OH) -1

Chlorite

(ClO₂)  -1

Iodate

(IO₃) -1

Hypochlorite

(ClO) -1

 Permanganate

(MnO₄) -1

Dihydrogen Phosphate

(H₂PO₄) -1

Carbonate

(CO₃) -2

Chromate

(CrO₄) -2

Dichromate

(Cr₂O₇) -2

Hexafluorosilicate

(SiF₆) - 2

Oxalate

(C₂O₄) - 2

Selenate

(SeO₄) -2

Tartrate

(C₄H₄O₆) -2

Hydrogen Phosphate

(HPO₄) -2

 Sulfate

(SO₄)-2

Sulfite

(SO₃) -2

Peroxide

(O₂) -2

Arsenate

(AsO₄) -3

Phosphate

(PO₄) -3

Phosphite

(PO₃) - 3

Pyrophosphate

(P₂O₇) -4

How do you determine charges in Metals

Group Number = charge

How do you determine charges in Non-metals

8 minus the Group number