Considering the various representatives of the salt class, they are:
1. Oxygen-containing (salts of sulfuric, nitric, silicic and other acids, the composition of the acid residue of which includes oxygen and another non-metal).
2. Oxygen free, i.e., salts formed by the reaction of an acid whose acid residue does not contain oxygen are hydrochloric, hydrobromic, hydrogen sulfide, and others.
By the number of substituted hydrogens:
1. Monobasic: hydrochloric, nitric, hydroiodic and others. The composition of the acid is one hydrogen ion.
2. Dibasic: two hydrogen ions replaced by metal ions during salt formation. Examples: sulfuric, sulfurous, hydrogen sulfide and others.
3. Tribasic: in the acid composition, three hydrogen ions are replaced by metal ions: phosphoric.