Iron oxyacid salts

The oxyacid salts of iron(III) are more numerous than those of iron(II). Among the former, the sulfates arc of interest because of the readiness with which iron(III) sulfate replaces aluminum sulfate in the alums, which are hydrated double sulfates formed by certain trivalent and alkali metal (and other monovalent) sulfates. Iron(lII) sulfate, Fe2(SOa)s, is isomorphous with aluminum sulfate, AbfSOa).), because the radius of the Fe3+ ion is so dose to that of the Al3+ ion (0.57 A). For that reason, the isomorphous relationship extends to other salts, i.e the fluorides and some of the nitrates. 

Iron(II) Salts of Oxyacids and Other Anions [Fe(H20)6]SiF6... 

The oxyacids of pentavalent phosphorus are surprisingly numerous, and their chemistry is very complex. These considerations have only begun to be appreciated in recent years, when research has been stimulated by the discovery of important applications for the salts of these acids. The main application of the soluble phosphates is in water conditioning. Many of them possess the property of combining with calcium and magne- sium ions to form extremely stable soluble complexes that do not give precipitates with soap and do not deposit scale in boilers. Similar complexes are formed with iron, and stable soluble phosphates of iron find application in nutrition. Other uses for soluble phosphates are found in the textile industry, paints, and insecticide sprays. 

The oxyacids of sulfur such as sulphite, bisulfite, bisulfate, thiosulfate, metabisulfite, and dithionate proved to be efficient reducing agents in the redox-initiated polymerization of vinyl monomers. Numerous articles in these areas have been reported in the literature. Palit et al. [161-164] and Roskin et al. [165-167] have reported the polymerization of vinyl monomers using the persulfate-dithionate redox system. Chaddha et al, [168] also reported the persulfate-sulfide redox system to initiate polymerization. The use of sulfide [169,170] and dithionate [171] as reducing agents in conjunction with organic hydroperoxide, like cumene hydroperoxide and iron salt in emulsion... 

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