The pyrosulphate and related ions

The pyrosulphate and related ions The three related ions 

In (N02)(HS207) and 864(118207)2 (q.v.) the anion consists of a chain of hydrogen-bonded S2O7H ions  

The trisulphate and pentasulphate ions, S3O10 and 85O16, have been studied in the K salts but accurate bond lengths were not determined in the former ion.  

The 8204 ion exists in sodium dithionite, the reducing agent, hydrosulphite . This salt is prepared from the Zn salt, which results from the reduction of SO2 by Zn dust in aqueous suspension. In solution it rapidly decomposes to disulphite and thiosulphate 2S2O4 - 8205 + 8203 The structure of this ion is rather extraordinary (Fig. 16.6(a)). It has an eclipsed configuration with the planes of 

If a solution of K28O3 is saturated with SO2 the salt K282OS maybe crystallized 

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