Arsine Solid

Methylarsine, trifluoromethylarsine, and bis(trifluoromethyl)arsine [371-74-4] C2HAsF, are gases at room temperature all other primary and secondary arsines are liquids or solids. These compounds are extremely sensitive to oxygen, and ia some cases are spontaneously inflammable ia air (45). They readily undergo addition reactions with alkenes (51), alkynes (52), aldehydes (qv) (53), ketones (qv) (54), isocyanates (55), and a2o compounds (56). They also react with diborane (43) and a variety of other Lewis acids. Alkyl haUdes react with primary and secondary arsiaes to yield quaternary arsenic compounds (57). 

A sample of gaseous arsine, AsH3, in a 500.0-mL flask at 300. Torr and 223 K, is heated to 473 K, at which temperature arsine decomposes to solid arsenic and hydrogen gas. The flask is then cooled to 273 K, at which temperature the pressure in the flask is 508 Torr. Has all the arsine decomposed Calculate the percentage of arsine molecules that have decomposed. 

Miller, G. A., Arsine and Phosphine Replacements for Semiconductor Processing, Solid State Technolo, pp. 59-60 (Aug. 1989)... 

CdjPj and CdjAs are low band gap semiconductors (0.5 and 0.1 eV, respectively). The bulk materials are black and start to absorb in the infrared. These materials have been prepared as colloids in alkaline solution by precipitation of Cd with phosphine and arsine Depending on the conditions of preparation, particles of different sizes (between about 2 and 10 nm) were obtained, which could also be recovered in the solid state after evaporation of the solvent. The color of these materials ranged from black to colorless with decreasing particle size, with all kinds of intermediate colors in the visible. 

Substances with high vapor pressure evaporate rapidly. Those with low vapor pressure evaporate slowly. The impact of vapor pressure on the rate of evaporation makes vapor pressure a very important property in considering the tactical use and duration of effectiveness of chemical agents. A potential chemical agent is valuable for employment when it has a reasonable vapor pressure. One with exceptionally high vapor pressure is of limited use. It vaporizes and dissipates too quickly. Examples are arsine and carbon monoxide. On the other hand, mechanical or thermal means may effectively aerosolize and disseminate solid and liquid agents of very low vapor pressure. Vapor pressure and volatility are related. Translated into volatility, vapor pressure is most understandable and useful. 

Bis(trimethylsilyl)arsine reacts with diethyl- or dimethylzinc to form different arsenide complexes with the structure dependent on the steric demands of the alkyl group. In the presence of both methyl and ethyl groups alkylzinc bis(trimethylsilylarsenide) forms which has a trimeric solid state structure (37) with a six-membered Zn3As3 and Zn-As distances with an average of 2.48 A.322... 

Reactive materials are solids that produce arsine on contact with moisture or acids. Binary munitions that mix these reactive materials with water or acid upon delivery have been developed. 

Arsine is nonpersistent and quickly dissipates or decomposes in the open environment. Solid agents will retain the potential to produce arsine (ASH3) until they react with water. 

Solid agents will react with water to form arsine gas. 

Arsine produces arsenic acids and other arsenic products. Solid agents will react with water to form arsine gas. 

Structural firefighters protective clothing is recommended for fire situations only it is not effective in spill situations or release events. Although arsine is primarily an inhalation hazard, decomposition products may pose a percutaneous risk. If chemical protective clothing is not available and it is necessary to rescue casualties from a contaminated area, then structural firefighters gear will provide limited skin protection. Contact with solids and solutions should be avoided. 

These ligands all form 1 1 complexes with platinum(II) halides which are non-conductors, monomeric and, in the solid state, contain one coordinated and two free double bonds. Proton n.m.r. data indicate that all three double bonds are equivalent in solution due to a rapid equilibrium between bonded and non-bonded —CH=CH2 groups. The phosphine and arsine complexes PtBraL (L = tvpp, tvpa) react with two equivalents of bromine giving what are believed to be platinum(II) species containing one coordinated double bond and two —CHBr-CHaBr groups arising from the saturation by bromine of the two free double bonds. 

Arsine is used as a reducing agent and to synthesize many organoarsine derivatives. It is also used as a doping agent for solid state electronic components. Earlier, it was used as a military poison gas. It does not occur freely in nature but is susceptible to form upon contact of arsenic compounds with acid in presence of a metal. Thus commercial acids stored in metal tanks and contaminated with arsenic impurities may produce arsine. 

Ferrostlicons are compds prepd by fusing iron and silica in an electric furnace at high temps. Some of the high silicon varieties, particularly 50/50 compd, are expl and are dangerous to transport and to handle. FeSi is of unknown toxicity. Moisture, steam, or water decompose it and impurities liberate phosphine and arsine with water. Expl and fire hazards are considered moderate and arise from the reaction with water. For shipping purposes FeSi with Sx 30—70% is considered a flammable solid and must carry yellow labels. If the Si is less than 30 or more than 70%, the material is not considered hazardous... 

Bis[l,2-phenylenebis(dimethylarsine)]gold(I) bis(pentafluorophenyl)aurate(I) is a white crystalline solid that melts at 178°C. It is soluble in acetone and dichloromethane, slightly soluble in diethyl ether, and insoluble in hexane. Its IR spectrum shows, along with those due to the pentafluorophenyl group (see Section B), strong absorptions at 745,590,435,365, and 350 cm "1 arising from the bis(arsine). In the cation the bis(arsine) acts as a chelate and therefore the cation contains a tetrahedral four-coordinated gold(I) atom.9... 

Calcium carbide desulfurization slag has a distinctive odor. Since pure acetylene is odorless, the odor must be produced by other trace constituents in the off-gases. A calcium carbide desulfurization slag sample from one ductile foundry was treated with water at a 1 1 solid-to-liquid ratio, and the gas was collected in a Tedlar bag for analysis by GC-MS. Several trace gases were identified, including arsine, divinyl sulfide (CHj-CH S, ethanethiol (ethyl mercaptan), methane, phosphine, and carbon monoxide. 

A chemical species on the top-most layer of the solid (i.e., a surface species) occupies a site. For example, an arsine molecule adsorbed on a surface occupies a site, and could be denoted AsH3(s). Another example of a surface species is a bare gallium atom, Ga(s), on the top layer of a gallium arsenide crystal. What happens if another species, say a gas-phase AsH3, lands on top of the Ga(s) As shown in Fig. 11.3, the gallium atom that was at the surface is buried it is no longer designated a surface species. In this nomenclature it has become a bulk species. 

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