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The thiosulfate ion is tetrahedral at the central S atom. The thiosulfate ion has C 3v symmetry. The external sulfur atom has a valence of 2 while the central sulfur atom has a valence of 6. The oxygen atoms have a valence of 2. The S-S distance of about 201 pm in sodium thiosulphate is appropriate for a single bond.
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.
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 ...
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.
A chemical reaction involving the replacement of oxygen to sulfur is called thionation or thiation. Thio- can be prefixed with di- and tri- in chemical nomenclature. The word derives from Ancient Greek θεῖον (theîon) 'sulfur' (which occurs in Greek epic poetry as θέ(ϝ)ειον , théweion and may come from the same root as Latin fumus ...
The S−H bond in thiols is weak compared to the O−H bond in alcohols. For CH 3 X−H, the bond enthalpies are 365.07 ± 2.1 kcal/mol for X = S and 440.2 ± 3.0 kcal/mol for X = O. [ 21 ] Hydrogen-atom abstraction from a thiol gives a thiyl radical with the formula RS • , where R = alkyl or aryl.
Covalent bonds often result in the formation of small collections of better-connected atoms called molecules, which in solids and liquids are bound to other molecules by forces that are often much weaker than the covalent bonds that hold the molecules internally together. Such weak intermolecular bonds give organic molecular substances, such as ...
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 ...