Sodium Sulphantimonate

The oxides of arsenic and antimony, and more particularly the higher oxides, are acidic in nature, and form salts with basic oxides. 

Sulphur, in accord with its similarity to oxygen, can be substituted for it in many of its compounds without essentially altering their chemical nature, and the compounds thus obtained have the same nomenclature as the corresponding oxygen compounds, except that the prefix thio or sulpho is used. Thus sulpho-salts are produced in the same manner as the oxy-salts above  

The sulpho-salts of arsenic, antimony, and stannic tin are particularly characteristic of these metals. (See Preparation 43 and Experiment 11, page 294.) They are easily produced, and all are soluble. They are stable in neutral or basic solutions, but are decomposed by acids, because the anions of the salts combine with hydrogen ions to produce the very weak sulpho-acids, which, being unstable, decompose at once into the sulphides of the metals and hydrogen sulphide  

Sodium sulphantimonate can be prepared from stibnite by the combined action of a solution of sodium sulphide and sulphur, 

The hydrolysis of this salt, which produces a dirty appearing reddish brown precipitate consisting of an indefinite mixture of Sb2S3 and Sb2C 6, may be prevented by an excess of sodium sulphide or by the presence of sodium hydroxide. 

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Materials sodium sulphantimonate, Na3SbS4-9H20, from pre-... 

Sodium nitrate (crude) P. 1 Sodium potassium tartrate P. 29 Sodium silicate P. 41 Sodium sulphantimonate P. 58 Sodium sulphide P. 57 Strontium sulphate (celestite) P. 20, 21... 

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