ARSENIC PENTASULPHIDE

Chemical Properties

ARSENIC PENTASULPHIDE is yellow or orange powder(s); stable in air up to 95°C; can be prepared by fusing As and S or by passing H2S through HCl solution of arsenic acid; used as a paint pigment, in light filters [HAW93] [KIR78]

Physical properties

Yellow-brown glassy amorphous solid; sublimes on heating; decomposes around 500°C; insoluble in cold water (~1.4 mg/L at 0°C); dissolves in alkalies and solutions of alkali metal sulfides, and in nitric acid.

Uses

• Used for preparation of glasses with small gold additions posessing photoluminescent and conductive properties
• Reactant for preparation of silver thioarsenate complex ethylenediammonium salt

Uses

ARSENIC PENTASULPHIDE is used for preparation of glasses with small gold additions posessing photoluminescent and conductive properties 1 Reactant for preparation of silver thioarsenate complex ethylenediammonium salt 2

Uses

In thin sheets as a light filter; in pigments.

Production Methods

Arsenic(V) sulfide, As4S10, is produced by fusing stoichiometric quantities of As and S powder or by precipitation from highly acidic arsenate(V) solution with H2S.

Preparation

Arsenic pentasulfide is prepared by precipitation from an acidic solution of orthoarsenic acid, H₃AsO₄, or arsenic pentachloride, AsCl₅ or any other soluble As(V) salt by passing hydrogen sulfide. It may be also prepared by heating a mixture of arsenic and sulfur, extracting the fused mass with ammonia solution and reprecipitating arsenic pentasulfide at low temperature by addition of HCl.