The binary compounds of Sulphur with Oxygen all possess acid properties; they may be represented (in part) as follows:—
| Sulphur. | Oxygen. | |||
| Hyposulphurous Acid | 2 | atoms. | 2 | atoms. |
| Sulphurous Acid | 1 | " | 2 | " |
| Hyposulphuric Acid | 2 | " | 5 | " |
| Sulphuric Acid | 1 | " | 3 | " |
In this case the Sulphuric and Sulphurous Acids had become familiarly known before the others, intermediate in composition, were discovered. Hence, to avoid the confusion which would result from changing the nomenclature, the new bodies are termed Hyposulphuric and Hyposulphurous (from ὑπο, under).
Nomenclature of Salts.—Salts are named according to the acid they contain; the termination ic being changed into ate, and ous into ite. Thus, Sulphuric Acid forms Sulphates; Nitric Acid, Nitrates; but Sulphurous Acid forms Sulphites, and Nitrous Acid, Nitrites.
In naming a salt, the base is always placed after the acid, the term oxide being omitted; thus. Nitrate of Oxide of Silver is more shortly known as "Nitrate of Silver," the presence of Oxygen being understood.
When there are two oxides of the same base, both of which are salifiable,—in naming the salts, the term proto is prefixed to the acid of the salt formed by the lowest, and per to that of the higher oxide; as, the Protosulphate of Iron, or Sulphate of the Protoxide; the Persulphate of Iron, or Sulphate of the Peroxide.
Many salts contain more than one atom of acid to each atom of base. In that case, the usual prefixes expressive of quantity are adopted: thus, the Bisulphate of Potash contains twice as much Sulphuric Acid as the neutral Sulphate, etc.
On the other hand, there are salts in which the base is in excess with regard to the acid, and which are usually known as "basic salts;" thus, the red powder which deposits from solution of Sulphate of Iron, is a basic Persulphate of Iron, or a Sulphate of the Peroxide of Iron with more than the normal proportion of oxide.
Nomenclature of the Hydracid Salts.—The composition of these salts being different from those formed by Oxygen Acids, the nomenclature varies also. Thus, in neutralizing Hydrochloric Acid with Soda, the product formed is not known as Hydrochlorate of Soda, but as Chloride of Sodium; this salt, and others of a similar constitution, being binary, and not ternary, compounds. The salt produced by Hydrochloric Acid and Ammonia however is often called "Muriate or Hydrochlorate of Ammonia," although more strictly it should be the Chloride of Ammonium.
ON SYMBOLIC NOTATION.