Английская Википедия:Disulfur decafluoride
Шаблон:Chembox Disulfur decafluoride is a chemical compound with the formula Шаблон:Chem2. It was discovered in 1934 by Denbigh and Whytlaw-Gray.[1] Each sulfur atom of the Шаблон:Chem2 molecule is octahedral, and surrounded by five fluorine atoms[2] and one sulfur atom. The two sulfur atoms are connected by a single bond. In the Шаблон:Chem2 molecule, the oxidation state of each sulfur atoms is +5, but their valency is 6 (they are hexavalent). Шаблон:Chem2 is highly toxic, with toxicity four times that of phosgene.
It is a colorless liquid with a burnt match smell similar to sulfur dioxide.[3]
Production
Disulfur decafluoride is produced by photolysis of Шаблон:Chem2:[4]
Disulfur decafluoride arises by the decomposition of sulfur hexafluoride. It is produced by the electrical decomposition of sulfur hexafluoride (Шаблон:Chem2)—an essentially inert insulator used in high voltage systems such as transmission lines, substations and switchgear. Шаблон:Chem2 is also made during the production of Шаблон:Chem2.
Properties
The S-S bond dissociation energy is 305 ± 21 kJ/mol, about 80 kJ/mol stronger than the S-S bond in diphenyldisulfide.
At temperatures above 150 °C, Шаблон:Chem decomposes slowly (disproportionation) into Шаблон:Chem and Шаблон:Chem:
Шаблон:Chem reacts with [[Tetrafluorohydrazine|Шаблон:Chem]] to give [[Difluoroamino sulfur pentafluoride|Шаблон:Chem]]. It reacts with Шаблон:Chem to form Шаблон:Chem in the presence of ultraviolet radiation.
In the presence of excess chlorine gas, Шаблон:Chem reacts to form sulfur chloride pentafluoride (Шаблон:Chem):
The analogous reaction with bromine is reversible and yields Шаблон:Chem.[5] The reversibility of this reaction can be used to synthesize Шаблон:Chem from Шаблон:Chem.[6]
Ammonia is oxidised by Шаблон:Chem into [[Thiazyl trifluoride|Шаблон:Chem]].[7]
Toxicity
Шаблон:Chem was considered a potential chemical warfare pulmonary agent in World War II because it does not produce lacrimation or skin irritation, thus providing little warning of exposure. Disulfur decafluoride is a colorless gas or liquid with a SO2-like odor.[8] It is about four times as poisonous as phosgene. Its toxicity is thought to be caused by its disproportionation in the lungs into Шаблон:Chem, which is inert, and Шаблон:Chem, which reacts with moisture to form sulfurous acid and hydrofluoric acid.[9]
See also
References
External links
Шаблон:Sulfur compounds Шаблон:Chemical agents
