Antimony hydrides reactions with

Certain volatile elements must be analyzed by special analytical procedures as irreproducible losses may occur during sample preparation and atomization. Arsenic, antimony, selenium, and tellurium are determined via the generation of their covalent hydrides by reaction with sodium borohydride. The resulting volatile hydrides are trapped in a liquid nitrogen trap and then passed into an electrically heated silica tube. This tube thermally decomposes these compounds into atoms that can be quantified by AAS. Mercury is determined via the cold-vapor... 

The kinetics of the thermally induced homogeneous decomposition of phosphine (PH3) have not yet been studied. The species PH2, PH and P2 are formed on flash photolysis of PH3 and could be identified by their absorption spectra63. There are proposals as to the mechanism of the consecutive process after the photochemical primary step, but nothing is known about the kinetic parameters of these reactions. With arsine and antimony hydride only the heterogeneous decomposition has been studied64,65. 

The hydrides of phosphorus, arsenic, and antimony thus form an interesting transition series. On similar sorts of surface antimony hydride is the least stable, decomposing with measurable speed at ordinary temperatures, and phosphine is the most stable, not decomposing at an appreciable rate below a red heat. Arsine occupies an intermediate position. At low temperatures the adsorption is considerable, and, as a result, the stibine decomposition requires the pn equation, while the more stable hydrides, which only decompose rapidly at higher temperatures where the adsorption is smaller, obey the unimolecular law. It is interesting, moreover, that with stibine itself the exponent n increases towards unity as the temperature at which the reaction takes place is raised. 

Ignition or explosive reaction with metals (e.g., aluminum, antimony powder, bismuth powder, brass, calcium powder, copper, germanium, iron, manganese, potassium, tin, vanadium powder). Reaction with some metals requires moist CI2 or heat. Ignites with diethyl zinc (on contact), polyisobutylene (at 130°), metal acetylides, metal carbides, metal hydrides (e.g., potassium hydride, sodium hydride, copper hydride), metal phosphides (e.g., copper(II) phosphide), methane + oxygen, hydrazine, hydroxylamine, calcium nitride, nonmetals (e.g., boron, active carbon, silicon, phosphoms), nonmetal hydrides (e.g., arsine, phosphine, silane), steel (above 200° or as low as 50° when impurities are present), sulfides (e.g., arsenic disulfide, boron trisulfide, mercuric sulfide), trialkyl boranes. 

SAFETY PROFILE Poison by ingestion and intraperitoneal routes. A trace mineral added to animal feeds. Potentially explosive reaction with charcoal + ozone, metals (e.g., powdered aluminum, copper), arsenic carbon, phosphoms, sulfur, alkali metal hydrides, alkaline earth metal hydrides, antimony sulfide, arsenic sulfide, copper sulfide, tin sulfide, metal cyanides, metal thiocyanates, manganese dioxide, phosphorus. Violent reaction with organic matter. When heated to decomposition it emits very toxic fumes of I and K2O. See also lODATES. 

SAFETY PROFILE Poison by inhalation. Potentially explosive decomposition at 200°C. Flammable when exposed to heat or flame. Explosive reaction with ammonia + heat, chlorine, concentrated nitric acid, ozone. Incompatible with oxidants. The decomposition products are hydrogen and metallic antimony. When heated to decomposition it emits toxic fumes of Sb. Used as a fumigating agent. See also ANTIMONY COMPOUNDS and HYDRIDES. 

In the reaction with halides of the less electropositive metals such as mercury,79 arsenic,80- 81 antimony,82 and indium,83 a stannane provides nucleophilic hydrogen and gives the new metal hydride (equation 15-27). Free radical inhibitors may be added to repress radical reaction of vinyl reactants. The preparation of vinylmercury hydride by this route involves the unusual use of tributyltin chloride as a solvent (equation 15-28).79 On the other hand, in the reactions of tributyltin hydride with Grignard reagents, RMgX, the hydrogen behaves as an electrophile towards R, and the Sn-Mg bonded compounds are formed.84... 

Antimony, arsenic, selenium, tellurium, bismuth and tin are able to form volatile hydrides by reaction with NaBH4. This property of these metals is used for the hydride atomizing technique. In this method, the metal hydrides are atomized in quartz cuvette by electrical heating. 

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