Arsenic (III) sulfide
| Crystal structure | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|||||||||||||||||||
| __ As 3+ __ S 2− | |||||||||||||||||||
| General | |||||||||||||||||||
| Surname | Arsenic (III) sulfide | ||||||||||||||||||
| other names |
|
||||||||||||||||||
| Ratio formula | As 2 S 3 | ||||||||||||||||||
| Brief description |
golden yellow odorless solid |
||||||||||||||||||
| External identifiers / databases | |||||||||||||||||||
|
|||||||||||||||||||
| properties | |||||||||||||||||||
| Molar mass | 246.04 g mol −1 | ||||||||||||||||||
| Physical state |
firmly |
||||||||||||||||||
| density |
3.43 g cm −3 |
||||||||||||||||||
| Melting point |
300 ° C |
||||||||||||||||||
| boiling point |
707 ° C |
||||||||||||||||||
| solubility |
almost insoluble in water (0.51 mg l −1 at 18 ° C) |
||||||||||||||||||
| safety instructions | |||||||||||||||||||
|
|||||||||||||||||||
| MAK |
not established as a carcinogen |
||||||||||||||||||
| Thermodynamic properties | |||||||||||||||||||
| ΔH f 0 |
−169.0 kJ / mol |
||||||||||||||||||
| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | |||||||||||||||||||
Arsenic (III) sulphide (also diarsentrisulphide or arsenic trisulphide ), yellow arsenic sulfur As 2 S 3 (molar mass: 246.02 g / mol), is a chemical compound consisting of the elements arsenic and sulfur .
Occurrence
As a mineral, it is in the form As 4 S 6 and is called auripigment .
presentation
Arsenic (III) sulphide is produced by the sublimation of arsenic acid with sulfur and is precipitated from the solution of arsenic acid using hydrogen sulphide .
properties
It is lemon yellow, opaque, shiny, and insoluble in water. It melts to a yellow-red liquid, evaporates at 700 ° C without decomposition and burns in the air to form arsenic trioxide and sulfur dioxide .
structure
In solid arsenic (III) sulfide is as As 2 S 3 in a polymeric structure before. Arsenic is a three bond, sulfur is a two bond. As 4 S 6 , which is present in the adamantane structure, is formed in the gas phase .
use
The metallurgical product, made from arsenic acid and sulfur melted together, often consists essentially only of arsenic acid with little more than 1% sulfur and comes on the market as yellow glass, yellow arsenic, yellow arsenic glass, royal yellow or yellow sulfur arsenic. When sulfuric acid is purified with hydrogen sulfide, it is obtained as a by-product.
It was used as a color pigment for yellow painters' paint and to lighten shellac .
In medicine it was used as a depilatory (Rhusma).
toxicity
Pure arsenic (III) sulfide is insoluble in water and acid and is non-toxic, as it is only absorbed in very small quantities by the body. However, since it is more or less contaminated with other arsenic compounds in practice, it is classified as toxic for technical use.
literature
- AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 91st – 100th, improved and greatly expanded edition. Walter de Gruyter, Berlin 1985, ISBN 3-11-007511-3 , p. 1046.
- Altmann: Chemisch-Technische Stoffwerte , 2nd edition, p. 28, Harri Deutsch Frankfurt 1987, ISBN 3-8171-1014-6
Individual evidence
- ↑ a b c d entry to arsenic (III) sulfide in the GESTIS database of IFA , accessed on January 8, 2020(JavaScript required) .
- ↑ a b c d data sheet arsenic (III) sulfide from AlfaAesar, accessed on December 15, 2010 ( PDF )(JavaScript required) .
- ↑ Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry arsenic compounds, with the exception of those named in this appendix in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
- ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-5.