Names | |
---|---|
Other names Arsenic(III) chloride, Arsenous trichloride, Arsine trichloride, Butter of arsenic, de Valagin's solution, Trichloroarsine | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.029.144 |
EC Number |
|
PubChem CID | |
RTECS number |
|
UNII | |
UN number | 1560 |
CompTox Dashboard (EPA) | |
| |
| |
Properties | |
AsCl3 | |
Molar mass | 181.28 g/mol |
Appearance | colourless oily liquid |
Density | 2.163 g/cm3, liquid |
Melting point | −16.2 °C (2.8 °F; 256.9 K) |
Boiling point | 130.2 °C (266.4 °F; 403.3 K) |
Hydrolyzes | |
Solubility | soluble in alcohol, ether, HCl, HBr, chloroform, CCl4 [1] |
-79.9·10−6 cm3/mol | |
Refractive index (nD) | 1.6006 |
Viscosity | 9.77 x 10−6 Pa s |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards | Very toxic, carcinogen, corrosive, decomposes on contact with water releasing HCl |
GHS labelling: | |
Danger | |
H301, H310, H314, H331, H350, H410 | |
P201, P202, P260, P261, P262, P264, P270, P271, P273, P280, P281, P301+P310, P301+P330+P331, P302+P350, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P311, P321, P322, P330, P361, P363, P391, P403+P233, P405, P501 | |
NFPA 704 (fire diamond) | |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 48 mg/kg |
LCLo (lowest published) | 100 mg/m3 (cat, 1 hr) 200 mg/m3 (cat, 20 min) 338 ppm (rat, 10 min) [2] |
NIOSH (US health exposure limits): | |
PEL (Permissible) | [1910.1018] TWA 0.010 mg/m3 [3] |
REL (Recommended) | Ca C 0.002 mg/m3 [15-minute] [3] |
IDLH (Immediate danger) | Ca [5 mg/m3 (as As)] [3] |
Related compounds | |
Other anions | Arsenic trioxide, Arsenic trifluoride |
Other cations | Antimony trichloride |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Arsenic trichloride is an inorganic compound with the formula AsCl3, also known as arsenous chloride or butter of arsenic. This poisonous oil is colourless, although impure samples may appear yellow. It is an intermediate in the manufacture of organoarsenic compounds. [4]
AsCl3 is a pyramidal molecule with C3v symmetry. The As-Cl bond is 2.161 Å and the angle Cl-As-Cl is 98° 25'±30. [5] [6] AsCl3 has four normal modes of vibration: ν1(A1) 416, ν2(A1) 192, ν3 393, and ν4(E) 152 cm−1. [7]
This colourless liquid is prepared by treatment of arsenic(III) oxide with hydrogen chloride followed by distillation:
It can also be prepared by chlorination of arsenic at 80–85 °C, but this method requires elemental arsenic. [4]
Arsenic trichloride can be prepared by the reaction of arsenic oxide and sulfur monochloride. This method requires simple apparatus and proceeds efficiently: [8]
A convenient laboratory method is refluxing arsenic(III) oxide with thionyl chloride: [9]
Arsenic trichloride can also be prepared by the reaction of hydrochloric acid and arsenic(III) sulfide.
Hydrolysis gives arsenous acid and hydrochloric acid:
Although AsCl3 is less moisture sensitive than PCl3, it still fumes in moist air. [10]
AsCl3 undergoes redistribution upon treatment with As2O3 to give the inorganic polymer AsOCl. With chloride sources, AsCl3 also forms salts containing the anion [AsCl4]−. Reaction with potassium bromide and potassium iodide give arsenic tribromide and arsenic triiodide, respectively.
AsCl3 is useful in organoarsenic chemistry, for example triphenylarsine is derived from AsCl3: [11]
The chemical weapons called Lewisites are prepared by the addition of arsenic trichloride to acetylene:
Inorganic arsenic compounds are highly toxic, [4] and AsCl3 especially so because of its volatility and solubility (in water).
It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities. [12]
Samarium(III) chloride, also known as samarium trichloride, is an inorganic compound of samarium and chloride. It is a pale yellow salt that rapidly absorbs water to form a hexahydrate, SmCl3.6H2O. The compound has few practical applications but is used in laboratories for research on new compounds of samarium.
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula AlCl3. It forms a hexahydrate with the formula [Al(H2O)6]Cl3, containing six water molecules of hydration. Both the anhydrous form and the hexahydrate are colourless crystals, but samples are often contaminated with iron(III) chloride, giving them a yellow colour.
Manganese(II) chloride is the dichloride salt of manganese, MnCl2. This inorganic chemical exists in the anhydrous form, as well as the dihydrate (MnCl2·2H2O) and tetrahydrate (MnCl2·4H2O), with the tetrahydrate being the most common form. Like many Mn(II) species, these salts are pink, with the paleness of the color being characteristic of transition metal complexes with high spin d5 configurations.
Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl. The substance is a white solid sparingly soluble in water, but very soluble in concentrated hydrochloric acid. Impure samples appear green due to the presence of copper(II) chloride (CuCl2).
Chromium(III) chloride (also called chromic chloride) is an inorganic chemical compound with the chemical formula CrCl3. It forms several hydrates with the formula CrCl3·nH2O, among which are hydrates where n can be 5 (chromium(III) chloride pentahydrate CrCl3·5H2O) or 6 (chromium(III) chloride hexahydrate CrCl3·6H2O). The anhydrous compound with the formula CrCl3 are violet crystals, while the most common form of the chromium(III) chloride are the dark green crystals of hexahydrate, CrCl3·6H2O. Chromium chlorides find use as catalysts and as precursors to dyes for wool.
Iron(II) chloride, also known as ferrous chloride, is the chemical compound of formula FeCl2. It is a paramagnetic solid with a high melting point. The compound is white, but typical samples are often off-white. FeCl2 crystallizes from water as the greenish tetrahydrate, which is the form that is most commonly encountered in commerce and the laboratory. There is also a dihydrate. The compound is highly soluble in water, giving pale green solutions.
Phosphorus pentachloride is the chemical compound with the formula PCl5. It is one of the most important phosphorus chlorides/oxychlorides, others being PCl3 and POCl3. PCl5 finds use as a chlorinating reagent. It is a colourless, water-sensitive solid, although commercial samples can be yellowish and contaminated with hydrogen chloride.
Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic and reacts readily with water to release hydrogen chloride.
Rhodium(III) chloride refers to inorganic compounds with the formula RhCl3(H2O)n, where n varies from 0 to 3. These are diamagnetic solids featuring octahedral Rh(III) centres. Depending on the value of n, the material is either a dense brown solid or a soluble reddish salt. The soluble trihydrated (n = 3) salt is widely used to prepare compounds used in homogeneous catalysis, notably for the industrial production of acetic acid and hydroformylation.
Gold(III) chloride, traditionally called auric chloride, is an inorganic compound of gold and chlorine with the molecular formula Au2Cl6. The "III" in the name indicates that the gold has an oxidation state of +3, typical for many gold compounds. It has two forms, the monohydrate (AuCl3·H2O) and the anhydrous form, which are both hygroscopic and light-sensitive solids. This compound is a dimer of AuCl3. This compound has a few uses, such as an oxidizing agent and for catalyzing various organic reactions.
Ruthenium(III) chloride is the chemical compound with the formula RuCl3. "Ruthenium(III) chloride" more commonly refers to the hydrate RuCl3·xH2O. Both the anhydrous and hydrated species are dark brown or black solids. The hydrate, with a varying proportion of water of crystallization, often approximating to a trihydrate, is a commonly used starting material in ruthenium chemistry.
Phosphoryl chloride is a colourless liquid with the formula POCl3. It hydrolyses in moist air releasing phosphoric acid and fumes of hydrogen chloride. It is manufactured industrially on a large scale from phosphorus trichloride and oxygen or phosphorus pentoxide. It is mainly used to make phosphate esters.
Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis. Samples often appear red or orange owing to an impurity of vanadium tetrachloride.
Antimony trichloride is the chemical compound with the formula SbCl3. It is a soft colorless solid with a pungent odor and was known to alchemists as butter of antimony.
Gallium(III) chloride is an inorganic chemical compound with the formula GaCl3 which forms a monohydrate, GaCl3·H2O. Solid gallium(III) chloride is a deliquescent white solid and exists as a dimer with the formula Ga2Cl6. It is colourless and soluble in virtually all solvents, even alkanes, which is truly unusual for a metal halide. It is the main precursor to most derivatives of gallium and a reagent in organic synthesis.
Triphenylarsine is the chemical compound with the formula As(C6H5)3. This organoarsenic compound, often abbreviated AsPh3, is a colorless crystalline solid that is used as a ligand and a reagent in coordination chemistry and organic synthesis. The molecule is pyramidal with As-C distances of 1.942–1.956 Å and C-As-C angles of 99.6–100.5°.
Thiophosphoryl chloride is an inorganic compound with the chemical formula PSCl3. It is a colorless pungent smelling liquid that fumes in air. It is synthesized from phosphorus chloride and used to thiophosphorylate organic compounds, such as to produce insecticides.
Organoarsenic chemistry is the chemistry of compounds containing a chemical bond between arsenic and carbon. A few organoarsenic compounds, also called "organoarsenicals," are produced industrially with uses as insecticides, herbicides, and fungicides. In general these applications are declining in step with growing concerns about their impact on the environment and human health. The parent compounds are arsane and arsenic acid. Despite their toxicity, organoarsenic biomolecules are well known.
Methyldichloroarsine, sometimes abbreviated "MD" and also known as methyl Dick, is an organoarsenic compound with the formula CH3AsCl2. This colourless volatile liquid is a highly toxic vesicant that has been used in chemical warfare.
Lanthanide trichlorides are a family of inorganic compound with the formula LnCl3, where Ln stands for a lanthanide metal. The trichlorides are standard reagents in applied and academic chemistry of the lanthanides. They exist as anhydrous solids and as hydrates.