Calcium thiosulfate.hexahydrate

BeH808Se beryllium selenate tetrahydrate 10039-31-3 25.00 2.0300 1 745 CaH1209S2 calcium thiosulfate hexahydrate 10124-41-1 25.00 1.8700 1... 

The most common form of calcium thiosulfate is the hexahydrate [10035-02-6] CaS202 6H20, which has triclinic crystals and a density of 1.872 g/cm at 16°C (84). Heating, however, does not give the anhydrous salt because of decomposition at 80°C. At lower temperatures, dehydration stops at the monohydrate [15091-91-5]. The solubiUty of calcium thiosulfates in water is as follows ... 

Calcium thiosulfate [10124-41-1] M 152.2, m 43-49°, pK 0.6, pK 1.74 (for H2S2O3). Reciystallise the thiosulfate from water below 60° in a N2 atmosphere, followed by drying with EtOH and Et20. Store it in a refrigerator. The hexahydrate can decompose spontaneously at 43-49°. Store it in a cool closed container. [Pethybridge Taba JC/ e/w Soc, Faraday Trans 7 78 1331 1982.]... 

Many other metal thiosulfates, eg, magnesium thiosulfate [10124-53-5] and its hexahydrate [13446-30-5] have been prepared on a laboratory scale, but with the exception of the calcium, barium [35112-53-9] and lead compounds, these are of Httle commercial or technical interest. Although thaHous [13453-46-8] silver, lead, and barium thiosulfates are only slightly soluble, other metal thiosulfates are usually soluble in water. The lead and silver salts are anhydrous the others usually form more than one hydrate. Aqueous solutions are stable at low temperatures and in the absence of air. The chemical properties are those of thiosulfates and the respective cation. 

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