Hyposulfurous acid

HiSOj Hyposulfurous acid. HaSOs Sult urous acid. HaSO. Sulfuric acid. 

HaSaOj Pyrosulfuric acid. HaSaOa Dithionic acid. HaSaO, Trithionic acid. HaS,0 Tetrathionic acid. HaSsOe Pentathionic acid. 

Hyposulfurous Acid—HaSO,—66.—Hydrosulfurom aoid—ls an unstable body only known in solution, obtained by the action of zinc upon solution of sulfui-ous acid. It is a powerful bleaching and deoxidizing agent. 

Sulfurous Acid—HaSOs—83.—Although sulfurous acid has not been isolated, it, in all probability, exists in the acid solution, formed when sulfur dioxid is dissolved in water SOa -t- HaO = SOjHa. Its salts, the sulfites, are well defined. From the existence of certain organic derivatives (see sulfonic acids) it would seem that two isomeric modifications of the acid may exist. They are distinguished as the symmetrical, in which the S atom is quadrivalent, 

Sulfites,—The sulfites are decomposed by the stronger acids, with evolution of sulfur dioxid. Nitric acid oxidizes them to sulfates. The sulfites of the alkali metals are soluble, and are active reducing agents. 

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HYPOSULFUROUS ACID AND HYPOSUI.FITES. Hyposulfurous acid H S Oj is a yellow solution rapidly oxidized in air lo sulfurous acid and then to sulfuric acid. Commercially known as hydrosulfurous acid and its salts as hydrosullites (but not to be confused with "hypo which is sodium thiosulfate). 

Hyposulfurous acid is a powerful reducing agent, e.g., with copper sulfate forms cuprous hydride Cu H , brown precipitate, which evolves hydrogen gas and leaves copper on warning, with silver nitrate yields finely divided silver, with permanganate yields manganous compounds. Hyposulfurous acid is formed by reaction of sodium hyposuliile and an acid. 

Thiosulfuric Acid.—Hyposulfurous acid——114—maybe considered as sulfuric acid, HaSOi, in which one atom of oxygen has been replaced by one of sulfur. The acid itself has. not been isolated, being decomposed, on liberation from the thiosulfates, into sulfur, water and sulfur dioxid HiSjOa = S-f-80, + H,0. 

Sulfinic acids—are the acid ethers of hyposulfurous acid /H... 

But careful study of his myriad formulas leaves no doubt that he was most strongly influenced by Gerhardtian molecular positivism. His formulas were constructed to create an equal number of prime marks on both sides of the bracket, not to express presumed sequential physical arrangements of atoms within the molecule—much less any presumed linking function of atoms or radicals. For example, for hyposulfuric acid, sodium hyposulfite, anhydrous carbonic and sulfuric acids, and metaphosphoric acid, he wrote ... 

Marignac investigated erbium precipitates and found that they were not homogeneous. Two elements were present. One formed red salts with a characteristic absorption spectrum, while compounds of the other element were colorless. The element with the red color kept the name erbium, the other he called ytterbium. The discovery was made in 1878 and separation was possible by addition of hyposulfurous acid to chloride solutions. The erbium precipitated but not the ytterbium. The two elements erbium and ytterbium also appeared to be mixed, and research had to continue. 

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