Polyatomic Ions

Acetate

Acetate

C₂H₃O₂⁻

Carbonate

CO₃²⁻

Hydrogen carbonate/bicarbonate

HCO₃⁻

Hydroxide

OH⁻

Nitrite

NO₂⁻

Nitrate

NO₃⁻

Chromate

CrO₄²⁻

Dichromate

Cr₂O₇²⁻

Phosphate

PO₄³⁻

Hydrogen phosphate

HPO₄²⁻

Dihydrogen phosphate

H₂PO₄⁻

Ammonium

NH₄⁺

Hypochlorite

ClO-

Chlorite

ClO2-

Chlorate

ClO3-

Perchlorate

ClO4-

Permanganate

MnO₄⁻

Sulfite

SO₃²⁻

Hydrogen sulfite/bisulfite

HSO3-

Sulfate

SO₄²⁻

Hydrogen sulfate/bisulfate

HSO₄⁻

Cyanide

CN⁻

Peroxide

O2 2-

Hydronium

H3O+

Chromium

Cr 2+

Cr 3+

Iron

Fe 2+

Fe 3+

Cobalt

Co 2+

Co 3+

Copper

Cu +

Cu 2+

Tin

Sn 2+

Sn 4+

Mercury

Hg 2 2+

Hg 2+

Empirical formula

The lowest whole-number ratio of atoms of each element found in a compound

Molecular formula

Number of atoms in each element found in one molecule of the compound

Systematic names

Names using roman numerals (I, II, III)

Name of the compound

Use of the greek prefix (di, tetra)

Ionic - metal/nonmetal

“Calcium iodide”

“Iron(III) chloride”

Molecular - nonmetals only

“Diphosphorous pentoxide”

• Greek prefixes