AsCl3 ARSENIC TRICHLORIDE

AsCl3 ARSENIC TRICHLORIDE 63.784 5.9075E-02 -6.9453E-05 3.5616E-08 -6.6261E-12 298 2000 gas... 

Arsenic trichloride is a Lewis acid, shown by its formation of adducts with bases, e.g. Me3N AsCl3 (21), a trigonal bipyramid with a stereoactive lone pair on arsenic.601 The d(As—N) is exceptionally long and may be considered to have some ionic character. 

The vapour density of arsenic trichloride was found by Dumas 5 to be 6-301 (air = l), which value agrees with that required by the formula AsCl3 (=6-27). 

Arsenic trichloride (arsenic(HI) chloride), AsCl3, is the most common and important halide of arsenic. It may be formed by spontaneous combination of the elements and, in addition, by the following reactions (7) chlorine with arsenic trioxide (2) sulfur monochloride, S2Cl2, or a mixture of S2Q2 and chlorine, with arsenic trioxide and (3) arsenic trioxide with concentrated hydrochloric acid or with a mixture of sulfuric acid and a chloride. 

In the former reaction the main product is chloro(j3-chlorovinyl)methyl-arsine. In the latter triphenylarsine is produced in low yield together with traces of the compounds (CHCl=CH) AsCl3 and the remaining phenyl-arsines are produced in approximately equal amounts. The aluminum trichloride catalyst probably also helps the redistribution reactions (see Section II, A, 6,e). Long-chain acetylene derivatives also react with chloro-arsines in the same way 3,186), but complex products are obtained from tetrolic acid and arsenic trichloride 187). Hexafluorobut-2-yne does not react with arsenic trichloride although it does so with chlorodimethylarsine on heating or ultraviolet irradiation 188). 

The following is an example of eq. [8.1.12] In the mixture AsCl3-SnCl4, starmorrs tetrachloride is a base and arsenic trichloride is an acid ... 

Arsenic forms a volatile trifluoride, AsF3, and a fairly volatile trichloride, AsCl3, which fumes in air. The latter is prepared by passing dry hydrogen chloride over arsenic(lll) oxide at 500 K ... 

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