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Thiosulfate (IUPAC-recommended spelling; sometimes thiosulphate in British English) is an oxyanion of sulfur with the chemical formula S 2 O 2− 3.Thiosulfate also refers to the compounds containing this anion, which are the salts of thiosulfuric acid, such as sodium thiosulfate Na 2 S 2 O 3 and ammonium thiosulfate (NH 4) 2 S 2 O 3.
Eventually, [these] thioesters could have served to usher in ATP through its ability to support the formation of bonds between phosphate groups. However, due to the high free energy change of thioester's hydrolysis and correspondingly their low equilibrium constants, it is unlikely that these compounds could have accumulated abiotically to any ...
Conversion of simple disulfides to thiosulfinates results in a considerable weakening of the S–S bond from about 47.8 to 28.0 kcal mol −1 for the S-S bond in PhS(O)SPh and from about 63.2 to 39.3 kcal mol −1 for the S-S bond in MeS(O)SMe, [14] with the consequence that most thiosulfinates are both unstable and quite reactive.
In the solid state, the thiosulfate anion is tetrahedral in shape and is notionally derived by replacing one of the oxygen atoms by a sulfur atom in a sulfate anion. The S-S distance indicates a single bond, implying that the terminal sulfur holds a significant negative charge and the S-O interactions have more double-bond character.
Its bulk properties partly result from the interaction of its component atoms, oxygen and hydrogen, with atoms of nearby water molecules. Hydrogen atoms are covalently bonded to oxygen in a water molecule but also have an additional attraction (about 23.3 kJ·mol −1 per hydrogen atom) to an adjacent oxygen atom in a separate molecule. [2]
Sulfides, formerly known as thioethers, are characterized by C−S−C bonds [3] [4] Relative to C−C bonds, C−S bonds are both longer, because sulfur atoms are larger than carbon atoms, and about 10% weaker. Representative bond lengths in sulfur compounds are 183 pm for the S−C single bond in methanethiol and 173 pm in thiophene.
Treatment of sulfur with hydrogen gives hydrogen sulfide.When dissolved in water, hydrogen sulfide is mildly acidic: [5] H 2 S ⇌ HS − + H +. Hydrogen sulfide gas and the hydrosulfide anion are extremely toxic to mammals, due to their inhibition of the oxygen-carrying capacity of hemoglobin and certain cytochromes in a manner analogous to cyanide and azide.
One problem with this alternative process is the high consumption of thiosulfate, which is more expensive than cyanide. Another issue is the lack of a suitable recovery technique since [Au(S 2 O 3 ) 2 ] 3− does not adsorb to activated carbon , which is the standard technique used in gold cyanidation to separate the gold complex from the ore ...