Arsenious oxide, sublimation

At red heat arsenious oxide sublimes, leaving a dark blue residue. [Pg.65]

Arsenic III oxide (arsenic trioxide, arsenious oxide) [1327-53-3] M 197.8, three forms m 200°(amorphous glass), m 275°(sealed tube, octahedral, common form, sublimes > 125° without fusion but melts under pressure), m 312°, pKj 9.27, pK 13.54, pK 13.99 (for H3ASO3). Crystd in octahedral form from H2O or from dil HCl (1 2), washed, dried and sublimed (193°/760mm). Analytical reagent grade material is suitable for use as an analytical standard after it has been dried by heating at 105° for l-2h or has been left in a desiccator for several hours over cone H2SO4. POISONOUS (particulary the vapour, handle in a ventilated fume cupboard). [Pg.397]

Sublimation differs from ordinary distillation because the vapour condenses to a solid instead of a liquid. Usually, the pressure in the heated system is diminished by pumping, and the vapour is condensed (after travelling a relatively short distance) on to a cold finger or some other cooled surface. This technique, which is applicable to many organic solids, can also be used with inorganic solids such as aluminium chloride, ammonium chloride, arsenious oxide and iodine. In some cases, passage of a stream of inert gas over the heated substance secures adequate vaporisation. [Pg.11]

Mercuric arsenide forms microscopic mamellated crystals. When dry it oxidises readily in the air to arsenious oxide and mercury. On heating it volatilises without melting, forming a sublimate of arsenic and mercury and a little arsenious oxide. The arsenide is therefore dried under diminished pressure. When heated with an alkyl iodide, a diarsonium mercuriodide of the type As2R6I2.2HgI2 is formed.8... [Pg.71]

Arsenic Suboxide ( ), As20, was considered by Berzelius 1 to constitute the superficial dark brown film which forms on arsenic owing to oxidation. Retgers 2 stated that the brown deposit which accompanies the mirror formed by sublimation of commercial arsenic was the suboxide. It was looked upon 3 as an intermediate product in the oxidation of arsenic, but the material so described was undoubtedly a mixture of arsenic and arsenious oxide 4 or, in some cases, merely the amorphous variety of arsenic. [Pg.123]

The acidity of arsenious acid in aqueous solution is increased by the addition of mannitol, sorbitol or a-mannitan, probably owing to the formation and superior ionisation of an acid of the type HAsD2 (D representing the diol residue).9 When sublimed arsenious oxide is heated with water on a water-bath for 5 hours, the dissolved acid has less than the normal acidity, but by boiling the solution for 7 hours under a reflux condenser it attains its original acidity. [Pg.140]

Water does not sensibly attack realgar (at boiling temperature a little arsenious oxide and hydrogen sulphide are produced 2), but steam reacts at red heat to give a sublimate of arsenious oxide and arsenious sulphide.3... [Pg.243]

If finely powdered realgar is heated with aqueous sodium sulphide in a sealed tube at 100° C., a thioarsenate is formed and arsenic, which may be contaminated with sulphur, is precipitated.12 Heated with arsenious oxide, metallic arsenic sublimes and sulphur dioxide is evolved.13... [Pg.243]

The primary arsenic-containing material is arsenious oxide obtained by separation from roaster or smelter fine gases. Metallic arsenic is obtained as sublimate by heating the oxide with carbon. [Pg.147]

Lolingite, FeAs2, occurs in Saxony and Norway in rhombic crystals. Hardness 5 to 5 5 density 6-8 to 8 7. Greyish m colour, it gives a greyish black streak. When heated in an open tube a white sublimate of arsenious oxide or white arsenic S5 is obtained in the absence of air metallic arsenic is volatilised to a dark sublimate. [Pg.27]

The Oxides and Acids of Arsenic. Arsenic trioxide (arsenious oxide, AS4OP,) is a white solid substance which sublimes readily, and is easily purified by sublimation. Its molecules have the same structure as phosphorus trioxide, shown in Figure 21-4. It is a violent poison, and is used as an insecticide and for preserving skins. [Pg.457]

Arsenic III oxide (arsenic trioxide, arsenious oxide) ]1327-53-3] M 197.8, three forms m 200"(amorphous glass), m 275"(sealed tube, octahedral, common form, sublimes > 125 ... [Pg.451]

The miners in Bohemia followed this health advice when handling arsenious cobalt ores. On roasting, arsenic oxide sublimated off and the remaining ore could be treated reasonably safely. The arsenic oxide was delivered to the pharmacies. [Pg.1014]

When heated, arsenious sulphide readily sublimes and fusion occurs, according to Borgstrom,8 at 320° C. Earlier determinations have put the melting point at 310°,9 300°10 and 325° C.11 Air must be excluded or oxidation occurs. Some degree of volatilisation may be observed at the ordinary temperature.12 According to Schuller,13 when... [Pg.246]

This metal is occasionally found native, but it is chiefly met with in combination with cohalt, nickel, and iron. When the arseniurets of these metals are heated to redness in a current of air, a great part of the arsenic, being volatile, rises in vapour, and is deposited in the cold part of the chimney in the form of white oxide of arsenic or arsenious acid, the well-known white arsenic of commerce. This substance is mixed with charcoal or black flux (a mixture of charcoal with carbonate of potash), and the mixture introduced into a medicine phial, filling it about one-third. The phial is then placed in sand, the sand reaching as high as the mixture, and gradually heated to low redness. The metal sublimes and condenses in he upper part of the phial, which, when cold, may be cut off. [Pg.185]

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