Arsenic hydrides oxidation

Aresenwasserstoff Argentinean Hemorrhagic Fever Arsenic Butter Arsenic Chloride Arsenic Dichloroethane Arsenic Hydride Arsenic Oxide Arsenic Sodium Oxide Arsenic Trichloride Arsenic Trihydride Arsenic Trioxide Arsenic(3+) Chloride... 

Arsenous Acid Anhydride Arsenous Chloride Arsenous Hydride Arsenous Oxide Anhydride Arsenous Trichloride Arsenous Trioxide Arsenowodor Arsenwasserstoff... 

Arsenic hydride. See Arsine Arsenic oxide, for oxidizing iron in glass, 7 343... 

ARSENIC HYDRIDE (7784-42-1) A thermallyunstable flammable gas. Violent reaction with acids, halogens, chlorine, oxidizers. This chemical is endothermic can be detonated by shock, elevated temperatures above (572°F/300°C), or powerful initiators. Exposure to light causes moist material to decompose with deposition of solid black arsenic. Low conductivity may cause the accumulation of static electrical charges, and cause ignition of its vapors. 

Atmospheric oxidation of arsenic hydrides and diarsines, usually violent, gives a mixture of products which can include the trivalent oxide and penta-valent acid (3, 329). Under controlled conditions tetraaryldiarsines take up one mole of oxygen per mole of diarsine 329). Atmospheric oxidation of other arsenic compounds, apart from those rich in alkyl groups with a small number of carbon atoms, is usually very much slower. [See also Section II, B,7]. 

Information from the WebElements site arsenic acid SeeARSENic(V) oxide. arsenic(lll) acid SeeARSENic(III) oxide. arsenic hydride SeeARSiNE. 

Arsenic fluoride. See Arsenic trifluoride Arsenic (V) fluoride. See Arsenic pentafluoride Arsenic hydride. See Arsine Arsenic, metallic. See Arsenic Arsenic oxide Arsenic (III) oxide. See Arsenic tri oxide... 

Arsenous anhydride. See Arsenic trioxide Arsenous chloride. See Arsenic trichloride Arsenous fluoride. See Arsenic trifluoride Arsenous hydride. See Arsine Arsenous oxide Arsenous oxide anhydride. 

Proust showed that the black tarnish forming on silver exposed to air is silver sulphide. He obtained lead dioxide (which he says was discovered by Scheele see p. 230) by the action of dilute nitric add on red lead, noticed the evolution of arsenic hydride when impure tin dissolves in acid, showed that the native oxychlorides of copper of Chile and Peru are definite compounds, rediscovered cuprous oxide, and prepared cuprous chloride he says that Pelletier had discovered stannous chloride and examined its action on solu-... 

A survey of the hydrides, oxides, hydroxides, and halides highlights the network components. The hydrides of nitrogen and phosphorus emphasize the uniqueness of the lightest element. Unlike the polar ammonia, the nonpolar phosphine is a poor base and not capable of forming hydrogen bonds. Arsine is less stable than phosphine, and its decomposition is the basis of the criminological Marsh test for the presence of arsenic. 

OrganometaUics and organometaHoids that yield peroxides in this manner include those in which Q is aluminum, antimony, arsenic, boron, cadmium, germanium, lead, phosphoms, siUcon, and tin and in which X is chlorine, bromine, alkoxy, acetoxy, cyano, oxide, hydride, hydroxyl, amino, alkyl, and boron tetrafluoride (28,33,44,60) (see Table 3). 

Copper sulfate, in small amounts, activates the zinc dust by forming zinc—copper couples. Arsenic(III) and antimony(TTT) oxides are used to remove cobalt and nickel they activate the zinc and form intermetaUic compounds such as CoAs (49). Antimony is less toxic than arsenic and its hydride, stibine, is less stable than arsine and does not form as readily. Hydrogen, formed in the purification tanks, may give these hydrides and venting and surveillance is mandatory. The reverse antimony procedure gives a good separation of cadmium and cobalt. 

This apparatus may also be adapted for what are termed hydride generation methods (which are strictly speaking flame-assisted methods). Elements such as arsenic, antimony, and selenium are difficult to analyse by flame A AS because it is difficult to reduce compounds of these elements (especially those in the higher oxidation states) to the gaseous atomic state. 

Zhang X, Cornelis R, De Kimpe J, and Mees L (1996) Arsenic speciation in serum of uraemic patients based on liquid chromatography with hydride generation atomic absorption spectrometry and on-line UV photo-oxidation digestion. Anal Chim Acta 319 177-185. 

With the exception of antimony (V), which requires the presence of iodide for its reduction, all species can be reduced in an acid medium at a pH of 1 -2. However, the reduction of some species, including antimony (III), arsenic (III), and all tin species, will also proceed at higher pH, where arsenic (V) and antimony (V) are not converted to their hydrides. This effect permits the selective determination of the various oxidation states of these elements [714, 716]. In the case of tin, reduction can be achieved at the pH of the Tris-HCl... 

Braman et al. [34] used sodium borohydride to reduce arsenic and antimony in their trivalent and pentavalent states to the corresponding hydrides. Total arsenic and antimony are then measured by their spectral emissions, respectively, at 228.8 nm and 242.5 nm. Limits of detection are 0.5 ng for antimony and 1 ng for arsenic, copper, and silver. Oxidants interfere in this procedure. 

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