GENERAL SOLUBILITY RULES*

Solubility of Ionic Compounds

 

 

 

 

Soluble Compounds:

Exceptions:

 

1.    Almost all salts of sodium (Na+),

        potassium (K+) and ammonium   (NH4+).

 

 

2.    All chlorides (Cl-),`Bromides (Br-)

        and iodides (I-) [halide salts]                 

 

Halide salts of Ag+, Hg22+, Pb2+

3.     Compounds containing fluoride (F-)

Fluorides of Mg2+, Ca2+, Sr2+, Ba2+, Pb2+

 

4.      All nitrates (NO3-), chlorates (ClO3-),

perchlorates (ClO4- ), acetates (C2H3O2-)

 

Acetates of Ag+ and Hg22+ only

moderately soluble

5.       All sulfate salts (SO42-)     

Sr2+, Ba2+, Pb2+, (Ca2+, Ag+ are moderately

soluble)

 

 

 

 

Poorly Soluble Salts:

Exceptions:

6.    All carbonates (CO32-)                        

      Phosphates (PO43-)

      Chromates (CrO42-)   

      Oxalates (C2O42-)

 

Na+, K+, NH4+

 

7.     All sulfides      (S2-)  

Group 1 & 2 cations and NH4+

 

8.   All hydroxides (OH-) & oxides (O2-)

Group 1 & NH4+, (Ca2+, Sr2+ and Ba2+ are

Moderately soluble)

 

 

 

 

·                Adapted from Kotz & Treichel, 4th Ed., "Chemistry and Chemical Reactivity", p. 184.