Containers arsine

The hydrogen produced by this process is liable to fewer impurities than phen iron is used, but it is always add and liable to contain arsine if commercial sulphuric add is used. 

The hydrogen produced by this process is generally very pure, but, depending on the purity of the zinc, it is liable to contain arsine. As the gas is alkaline, owing to the caustic soda carried in suspension, it requires to be scrubbed to make it suitable for balloons and airships. 

James Marsh (c. 1790-Woolwich, 21 Jime 1846), of Woolwich Arsenal, had burnt the hydrogen containing arsine at a jet and held a piece of cold porcelain in the flame, when an arsenic mirror was deposited. A report on the various forms of the Marsh test was drawn up by Thenard, Dumas, Boussingault, and Regnault. Antimony hydride was discovered simultaneously and independently by Lewis Thompson, Pfaff and other chemists. 

Arsine is authorized for shipment in cylinders manufactured in compliance with TC/DOT specification 3A, 3AA, 3E, or 3AL and must not exceed 125-lb (57-kg) water capacity (nominal). Specification 3AL cylinders containing arsine may only be transported by highway and rail. Cylinder valves must be protected and sealed from leaks in accordance with 49 CFR 173.40 [5]. 

Arsenic present only in traces (in any form) can be detected by reducing it to arsine and then applying tests for the latter. In Marsh s test, dilute sulphuric acid is added dropwise through a thistle funnel to some arsenic-free zinc in a flask hydrogen is evolved and led out of the flask by a horizontal delivery tube. The arsenic-containing compound is then added to the zinc-acid solution, and the delivery tube heated in the middle. If arsenic is present, it is reduced to arsine by the zinc-acid reaction, for example ... 

Lead—antimony or lead—arsenic ahoys must not be mixed with lead—calcium (aluminum) ahoys in the molten state. Addition of lead—calcium—aluminum ahoys to lead—antimony ahoys results in reaction of calcium or aluminum with the antimony and arsenic to form arsenides and antimonides. The dross containing the arsenides and antimonides floats to the surface of the molten lead ahoy and may generate poisonous arsine or stibine if it becomes wet. Care must be taken to prevent mixing of calcium and antimony ahoys and to ensure proper handling of drosses. 

Primary and Secondary Arsines. Compared to the vast number of known organoarsenic compounds, relatively few primary (RASH2) and secondary (R2ASH) arsines have been described. Primary arsines are commonly prepared by the 2inc—hydrochloric acid reduction of substances containing... 

Trimethyl arsine [593-88-4] C H As, has been identified as the toxic volatile arsenical, once known as "Gosio gas," produced by the reaction of certain molds that grow on wallpaper paste and react with inorganic arsenic compounds present in the paper. A number of microorganisms can methylate arsenic trioxide and other arsenic-containing compounds to yield trimethylarsine. These microorganisms include Scopulariopsis brevicaulis Candida humicola and Gliocladium roseum (72). 

Both arsonic and arsinic acids give precipitates with many metal ions, a property which has found considerable use in analytical chemistry. Of particular importance are certain a2o dyes (qv) containing both arsonic and sulfonic acid groups which give specific color reactions with a wide variety of transition, lanthanide, and actinide metal ions. One of the best known of these dyes is... 

The final ceU product contains 250—300 g/L H2SO in the last stages of electrolyte purification, and antimony and bismuth precipitate, resulting in heavily contaminated cathodes that are recycled through the smelter. Arsenic and hydrogen evolved at the cathodes at these later stages react to form arsine, and hoods must be provided to collect the toxic gas. 

Arsine, AsHs, is formed when many As-containing compounds are reduced with nascent hydrogen and its decomposition on a heated glass surface to form a metallic mirror formed the basis of Marsh s test for the element. The low-temperature reduction of AsCls with LiAlH4 in diethyl ether solution gives good yields of the gas as does the dilute acid hydrolysis of many arsenides of electropositive elements (Na, Mg, Zn, etc.). Similar reactions yield stibine, e.g. ... 

A considerable number of the tertiary phosphine and arsine complexes of iridium(III) have been synthesized [4, 8] they generally contain 6-coordinate iridium and are conventionally prepared by refluxing Na2IrCl6 with the phosphine in ethanol or 2-methoxyethanol [154]... 

Many, but not all, bidentate phosphine and arsine ligands form 2 1 complexes with these metals. M(diars)2X2 (diars = o-C6H4(AsMe3)2) contain 6-coordinate metals frans-Pd(diars)2I2 has long Pd-I bonds (3.52 A). These complexes are 1 1 electrolytes in solution, suggesting the presence of 5-coordinate M(diars)2X+ ions. 

Organometallic intramolecular coordination compounds containing an arsine donor ligand. 

The element symbols within each formula are arranged according to a modified Hill system in which the order is metal(s), C, H and then any remaining symbols arranged alphabetically. Compounds containing two (or more) different metals appear twice (or more), being listed under each metal. Common ligand abbreviations which appear in the text have also been used in the index. These include acac (acetylacetone), bipy (2,2 -bipyridyl), diars [o-phenylenebis(dimethyl-arsine)], dien (diethylenetriamine), etc. 

Mass effects due to some ions in salts. It is generally observed that there is a greater instability amongst compounds containing heavy atoms compared with elements in the first periods of the periodic tabie.This can be observed by analysing enthalpies of formation of ammonia, phosphine, arsine and stibine (see previous table for the last three). In the same way, it is easier to handle sodium azide than lead azide, which is a primary explosive for detonators. It is exactly the same with the relatively highly stable zinc and cadmium thiocyanates and the much less stable mercury thiocyanate. 

In the presence of chlorine, the reaction is explosive. The same happens with concentrated nitric acid. In the latter case, the reaction is more violent than with arsine (that needs fuming nitric acid). Finally, it detonates when it is put in contact with oxygen containing 2% of ozone even at -90°C. 

The number of gold complexes containing tertiary phosphines, arsines, or stibines as ligands is large because of the wide use of the fragment AuL+, mainly with L = PPh3, in the synthesis of... 

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