Silver arsenic trisulfide

Arsen-saure, /, arsenic acid, -silber, n, silver arsenide, -silberblende,/, proustite, -spiegel, m. arsenic mirror, -suifid, n, arsenic sulfide, esp. the pentasulfide. -sulfur, n. arsenic trisulfide, arsenic(III) sulfide, -iir, n, (-ous) arsenide, -verbindung, /. arsenic compound, -vergiftung, /. arsenic poisoning, -wasser-stoff, m. arsenic hydride, arseniuretted hydrogen (specif, arsine, AsHa). -zink, n. zinc arsenide. 

Arsenic is a metallic element (symbol As atomic no. 33), which exists in several allotropic forms. Various ores contain crystalline forms of arsenic salts cobaltite contains cobalt arsenic sulfide mispickel (arsenopyrite) iron arsenic sulfide orpiment arsenic trisulfide proustite (ruby silver ore) silver arsenic sulfide realgar arsenic sulfide and tennantite copper arsenic sulfide. 

Colloid vibration potentials offer a means of measuring the zeta-potential, and hence charge, on colloid particles. Values of-KT4 Vein s at frequencies of a few hundred kilohertz seem to be typical of this effect, and a range of colloids were examined, including silver, silver iodide, and arsenic trisulfide. 

A test for AsgSs (and its differentiation from AsgSj) is described on page 85. It is based on the formation of a black product (HgS and Hg ) when this sulfide is heated with mercuric cyanide. The reaction can also be used to detect mercuric cyanide in the absence of silver and bismuth salts which react similarly with arsenic trisulfide. The use of AsgSj paper is recommended. 

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