Arsenic trisulfide

Arsenic trisulfide
Sample of arsenic trisulfide as orpiment mineral
Ball and stick unit cell model of polymeric arsenic trisulfide
Arsenic trisulfide
Names
Preferred IUPAC name
Arsenic trisulfide
Other names
  • Arsenic(III) sulfide
  • Orpiment
  • Sulphuret of arsenic
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.013.744 Edit this at Wikidata
EC Number
  • 215-117-4
RTECS number
  • CG2638000
UNII
  • InChI=1S/As4S6/c5-1-6-3-8-2(5)9-4(7-1)10-3 checkY
    Key: OUFDYFBZNDIAPD-UHFFFAOYSA-N checkY
  • InChI=1/As4S6/c5-1-6-3-8-2(5)9-4(7-1)10-3
    Key: OUFDYFBZNDIAPD-UHFFFAOYAM
  • S1[As]3S[As]2S[As](S[As]1S2)S3
Properties
As2S3
Molar mass 246.02 g·mol−1
Appearance yellow or orange crystals
Density 3.43 g/cm3
Melting point 310 °C (590 °F; 583 K)
Boiling point 707 °C (1,305 °F; 980 K)
insoluble
Solubility soluble in ammonia
−70.0·10−6 cm3/mol
Structure[1]
monoclinic
P21/n (No. 11)
a = 1147.5(5) pm, b = 957.7(4) pm, c = 425.6(2) pm
α = 90°, β = 90.68(8)°, γ = 90°
pyramidal (As)
Hazards
GHS labelling:[3][4]
Acute Tox. 3 Aquatic Acute 1, Aquatic Chronic 1
Danger
H300, H331, H400, H411
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
0
0
NIOSH (US health exposure limits):
PEL (Permissible)
[1910.1018] TWA 0.010 mg/m3[2]
REL (Recommended)
Ca C 0.002 mg/m3 [15-minute][2]
IDLH (Immediate danger)
Ca [5 mg/m3 (as As)][2]
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Arsenic trisulfide is the inorganic compound with the formula As2S3. It is a dark yellow solid that is insoluble in water. It also occurs as the mineral orpiment (Latin: auripigmentum), which has been used as a pigment called King's yellow. It is produced in the analysis of arsenic compounds. It is a group V/VI, intrinsic p-type semiconductor and exhibits photo-induced phase-change properties.[clarification needed]

  1. ^ Mullen, D. J. E.; Nowacki, W (1972), "Refinement of the crystal structures of realgar, AsS and orpiment, As2S3" (PDF), Z. Kristallogr., 136 (1–2): 48–65, Bibcode:1972ZK....136...48M, doi:10.1524/zkri.1972.136.1-2.48.
  2. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0038". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Index no. 033-002-00-5 of Annex VI, Part 3, to Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006. OJEU L353, 31.12.2008, pp 1–1355 at p 427.
  4. ^ "Arsenic, inorganic compounds (as As)", 29 C.F.R. § 1910.1018, 58 FR 35310, June 30, 1993, as amended. "Arsenic (inorganic compounds, as As)", Pocket Guide to Chemical Hazards, U.S. Department of Health and Human Services (NIOSH) Publication No. 2005-149, Washington, DC: Government Printing Office, 2005, ISBN 9780160727511.