Solubility Chart
Anion
Soluble Cations
Insoluble* Cations
Nitrate (NO3-)
Acetate (CH3COO-)
All common ions
No common ions
Chloride (Cl-)
Bromide (Br-)
Iodide (I-)
Most ions
Ag+, Pb2+, Hg+
Sulfate (SO42-)
Most ions
Ca2+, Ba2+, Sr2+, Ag+, Pb2+, Hg+
Carbonate (CO32-)
Sulfite (SO32-)
Phosphate (PO43-)
NH4+, Li+, Na+, K+
Most ions
Hydroxide (OH-)
NH4+, Ba2+, Li+, Na+, K+
Most ions
NH4+,
Most ions
Sulfide
(S2-)
Oxide (O2-)
Li+, Na+,
K+
Ca2+, Ba2+, Li+, Na+, K+ hydrolyse
Most ions
* Often, “insoluble” actually means “sparingly soluble” (dissolves to a small degree) rather than “completely unable to dissolve”.
All compounds of the ammonium ion (NH4+) and alkali metals (group I) cations are soluble.
All nitrates and acetates are soluble.
All chlorides, bromides and iodides are soluble EXCEPT those of silver, lead and mercury (I).
All sulfates are soluble EXCEPT those of calcium, barium, strontium, silver, lead and mercury (I).
All carbonates, sulfites and phosphates are insoluble EXCEPT those of ammonium and alkali metals (group I) cations.
All hydroxides are insoluble EXCEPT those of ammonium, barium and alkali metals (group I) cations.
All sulfides are insoluble EXCEPT those of ammonium and alkali metals (group I) cations.
All oxides are insoluble EXCEPT those of calcium, barium and alkali metal (group I) cations. These soluble ones actually
hydrolyse (react with the water to form hydroxides).