Common Ions

Monatomic Ions

1+

H⁺ hydrogen Li⁺ lithium Na sodium K+ potassium Rb+ rubidium Cs+ cesium Ag+ silver Cu+ copper(I)

2+

Mg2+ magnesium Ca2+ calcium Sr2+ strontium Ba2+ barium Zn2+ zinc Cd2+ cadmium Cr2+ chromium(II) Co2+ cobalt(II) Cu2+ copper(II) Fe2+ iron(II) Pb2+ lead(II) Mn2+ manganese(II) Hg2 2+ mercury(I) Hg2+ mercury(II) Sn2+ tin(II)

3+

Al3+ aluminum Bi3+ bismuth Cr3+ chromium(III) Co2+ cobalt(II) Fe3+ iron(III) Mn3+ manganese(III)

4+

Pb4+ lead(IV) Mn4+ manganese(IV) Sn4+ tin(IV)

1-

H- hydride F- fluoride Cl- chloride Br- bromide I- iodide

2-

O2- oxide S2- sulfide

3-

N3- nitride P3- phosphide

Polyatomic ions

Polyatomic Cations

NH4 + ammonium H3O+ hydronium

Polyatomic Anions

OH- hydroxide CN- cyanide O2 2- peroxide CO3 2- carbonate C2O4 2- oxalate NO2 - nitrite NO3 - nitrate PO3 3- phosphite PO4 3- phosphate SO3 2- sulfite SO4 2- sulfate S2O3 2- thiosulfate ClO- hypochlorite ClO2 - chlorite ClO3 - chlorate ClO4 - perchlorate CH3COO- or C2H3O2 - acetate AsO4 3- arsenate BO3 3- borate SiO3 2- silicate MnO4 - permanganate CrO4 2- chromate Cr2O7 2- dichromate CHO2 - formate HCO3 - hydrogen carbonate or bicarbonate HSO3 - hydrogen sulfite or bisulfite HSO4 - hydrogen sulfate or bisulfate HPO4 2- hydrogen phosphate H2PO4 - dihydrogen phosphate