List of common cations and anions

Cations

1+ 2+ 3+

H+ Hydrogen Mg

2+ Magnesium Al

3+ Aluminium

Li+ Lithium Ca

2+ Calcium Fe

3+ Iron(III)

Na+ Sodium Ba

2+ Barium Cr

3+ Chromium(III)

K+ Potassium Sr

2+ Strontium

Rb+ Rubidium Zn

2+ Zinc

Cs+ Cesium Cd

2+ Cadmium

NH4+ Ammonium Cu

2+ Copper(II)

Ag+ Silver Fe

2+ Iron(II)

Cu+ Copper(I) Pb

2+ Lead(II)

Co

2+ Cobalt(II)

Mn

2+ Manganese(II)

Sn

2+ Tin(II)

Anions

1- 2- 3-

F- Fluoride O

2- Oxide N

3- Nitride

Cl- Chloride S

2- Sulphide PO4

3- Phosphate

Br- Bromide CO3

2- Carbonate

I- Iodide SO4

2- Sulphate

OH- Hydroxide SO3

2- Sulphite

ClO3- Chlorate CrO4

2- Chromate

NO3- Nitrate Cr2O7

2- Dichromate

NO2- Nitrite HPO4

2- Hydrogen Phosphate

CN- Cyanide O2

2- Peroxide

H2PO4- Di-Hydrogen Phosphate

HCO3- Bicarbonate

HSO4- Bisulphate

SCN- Thiocyanate

MnO4- Permanganate

H- Anhydride

Note: Some cations particularly transition metal cations can have more than one charge, depending on

what other chemicals are around.

To differentiate between charges, we can use roman numerals to specify the charge.

For example, Fe(II) means that the iron cation has a charge of 2+, Fe2+

, whereas Fe(III) would be Fe3+

.

There are alternative names for these ions (ferrous and ferric iron respectively) that can be used too.

Ionic Solubility Table

Soluble ions Exceptions (insoluble)

Alkali metals (Li+, Na+, K+, Rb+, Cs+), ammonium (NH4+)

Nitrates (NO3-), bicarbonates (HCO3-), chlorates (ClO3-)

Chlorides, bromides, iodides (Cl-, Br-, I-) Ag+, Hg22+, Pb2+

Sulphates (SO42-) Ag+, Hg22+, Pb2+,

Ca2+, Sr2+, Ba2+

Insoluble ions Exceptions (soluble)

Carbonates (CO32-), sulphides (S2-), phosphates (PO43-), chromates (CrO42-)

Alkali metals and ammonium

Hydroxides (OH-) Alkali metals and barium (Ba2+)

Salts containing a soluble ion will remain dissolved unless mixed with an exception.

Salts containing an insoluble ion will precipitate out unless the only other ions present are exceptions.