Arsenic trifluoride

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Arsenic trifluoride
Arsenic(III)fluoride.svg
Arsenic-trifluoride-3D-balls.png
Names
IUPAC name
Arsenic(III) fluoride
Other names
Arsenic trifluoride, trifluoroarsane, TL-156
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.029.145 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 232-060-0
PubChem CID
RTECS number
  • CG5775000
UNII
  • InChI=1S/AsF3/c2-1(3)4 Yes check.svgY
    Key: JCMGUODNZMETBM-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/AsF3/c2-1(3)4
    Key: JCMGUODNZMETBM-UHFFFAOYAJ
  • F[As](F)F
Properties
AsF3
Molar mass 131.9168 g/mol
Appearancecolorless oily liquid
Density 2.666 g/cm3 (0 °C) [1]
Melting point −8.5 °C (16.7 °F; 264.6 K)
Boiling point 60.4 °C (140.7 °F; 333.5 K)
decomposes
Solubility soluble in alcohol, ether, benzene and ammonia solution
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Toxic, corrosive
GHS labelling:
GHS-pictogram-skull.svg
Danger
H301, H311, H331
P261, P264, P270, P271, P280, P301+P310, P302+P352, P304+P340, P311, P312, P321, P322, P330, P361, P363, P403+P233, P405, P501
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]
Thermochemistry
-821.3 kJ/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Arsenic trifluoride is a chemical compound of arsenic and fluorine with the chemical formula AsF3. It is a colorless liquid which reacts readily with water. [3]

Preparation and properties

It can be prepared by reacting hydrogen fluoride, HF, with arsenic trioxide: [3]

6HF + As2O3 → 2AsF3 + 3H2O

It has a pyramidal molecular structure in the gas phase which is also present in the solid. [3] In the gas phase the As-F bond length is 170.6 pm and the F-As-F bond angle 96.2°. [4]

Arsenic trifluoride is used as a fluorinating agent for the conversion of non-metal chlorides to fluorides, in this respect it is less reactive than SbF3. [3]

Salts containing AsF4 anion can be prepared for example CsAsF4. [5] the potassium salt KAs2F7 prepared from KF and AsF3 contains AsF4 and AsF3 molecules with evidence of interaction between the AsF3 molecule and the anion. [6]

AsF3 reacts with SbF5. The product obtained could be described as the ionic compound AsF2+ SbF6. However, the authors conclude the formed product cannot be viewed only as an ionic compound nor entirely as the neutral adduct AsF3SbF5. The crystal structure displays characteristics of both an ionic pair, and a neutral adduct, taking the middle ground in between both models. [7]

Related Research Articles

Calcium fluoride is the inorganic compound of the elements calcium and fluorine with the formula CaF2. It is a white insoluble solid. It occurs as the mineral fluorite (also called fluorspar), which is often deeply coloured owing to impurities.

Boron trifluoride is the inorganic compound with the formula BF3. This pungent, colourless, and toxic gas forms white fumes in moist air. It is a useful Lewis acid and a versatile building block for other boron compounds.

<span class="mw-page-title-main">Nickel(II) fluoride</span> Chemical compound

Nickel(II) fluoride is the chemical compound with the formula NiF2. It is an ionic compound of nickel and fluorine and forms yellowish to green tetragonal crystals. Unlike many fluorides, NiF2 is stable in air.

Antimony pentafluoride is the inorganic compound with the formula SbF5. This colourless, viscous liquid is a strong Lewis acid and a component of the superacid fluoroantimonic acid, formed upon mixing liquid HF with liquid SbF5 in 1:1 ratio. It is notable for its strong Lewis acidity and the ability to react with almost all known compounds.

<span class="mw-page-title-main">Hydrogen fluoride</span> Chemical compound

Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula HF. This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid. It is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers, e.g. polytetrafluoroethylene (PTFE). HF is widely used in the petrochemical industry as a component of superacids. Hydrogen fluoride boils at near room temperature, much higher than other hydrogen halides.

<span class="mw-page-title-main">Tetrafluoroborate</span> Anion

Tetrafluoroborate is the anion BF
4
. This tetrahedral species is isoelectronic with tetrafluoroberyllate (BeF2−
4
), tetrafluoromethane (CF4), and tetrafluoroammonium (NF+
4
) and is valence isoelectronic with many stable and important species including the perchlorate anion, ClO
4
, which is used in similar ways in the laboratory. It arises by the reaction of fluoride salts with the Lewis acid BF3, treatment of tetrafluoroboric acid with base, or by treatment of boric acid with hydrofluoric acid.

<span class="mw-page-title-main">Selenium tetrafluoride</span> Chemical compound

Selenium tetrafluoride (SeF4) is an inorganic compound. It is a colourless liquid that reacts readily with water. It can be used as a fluorinating reagent in organic syntheses (fluorination of alcohols, carboxylic acids or carbonyl compounds) and has advantages over sulfur tetrafluoride in that milder conditions can be employed and it is a liquid rather than a gas.

The bifluoride ion is an inorganic anion with the chemical formula [HF2]. The anion is colorless. Salts of bifluoride are commonly encountered in the reactions of fluoride salts with hydrofluoric acid. The commercial production of fluorine involves electrolysis of bifluoride salts.

Antimony trifluoride is the inorganic compound with the formula SbF3. Sometimes called Swarts' reagent, is one of two principal fluorides of antimony, the other being SbF5. It appears as a white solid. As well as some industrial applications, it is used as a reagent in inorganic and organofluorine chemistry.

<span class="mw-page-title-main">Hexafluorophosphate</span> Anion with the chemical formula PF6–

Hexafluorophosphate is an anion with chemical formula of [PF6]. It is an octahedral species that imparts no color to its salts. [PF6] is isoelectronic with sulfur hexafluoride, SF6, and the hexafluorosilicate dianion, [SiF6]2−, and hexafluoroantimonate [SbF6]. In this anion, phosphorus has a valence of 5. Being poorly nucleophilic, hexafluorophosphate is classified as a non-coordinating anion.

<span class="mw-page-title-main">Dioxygenyl</span> Chemical compound

The dioxygenyl ion, O+
2
, is a rarely-encountered oxycation in which both oxygen atoms have a formal oxidation state of +1/2. It is formally derived from oxygen by the removal of an electron:

<span class="mw-page-title-main">Manganese(IV) fluoride</span> Chemical compound

Manganese tetrafluoride, MnF4, is the highest fluoride of manganese. It is a powerful oxidizing agent and is used as a means of purifying elemental fluorine.

Arsenic pentafluoride is a chemical compound of arsenic and fluorine. It is a toxic, colorless gas. The oxidation state of arsenic is +5.

<span class="mw-page-title-main">Bismuth trifluoride</span> Chemical compound

Bismuth(III) fluoride or bismuth trifluoride is a chemical compound of bismuth and fluorine. The chemical formula is BiF3. It is a grey-white powder melting at 649 °C.

<span class="mw-page-title-main">Tetrafluoroammonium</span>

The tetrafluoroammonium cation is a positively charged polyatomic ion with chemical formula NF+
4
. It is equivalent to the ammonium ion where the hydrogen atoms surrounding the central nitrogen atom have been replaced by fluorine. Tetrafluoroammonium ion is isoelectronic with tetrafluoromethane CF
4
, trifluoramine oxide ONF
3
and the tetrafluoroborate BF
4
anion.

Fluorine forms a great variety of chemical compounds, within which it always adopts an oxidation state of −1. With other atoms, fluorine forms either polar covalent bonds or ionic bonds. Most frequently, covalent bonds involving fluorine atoms are single bonds, although at least two examples of a higher order bond exist. Fluoride may act as a bridging ligand between two metals in some complex molecules. Molecules containing fluorine may also exhibit hydrogen bonding. Fluorine's chemistry includes inorganic compounds formed with hydrogen, metals, nonmetals, and even noble gases; as well as a diverse set of organic compounds. For many elements the highest known oxidation state can be achieved in a fluoride. For some elements this is achieved exclusively in a fluoride, for others exclusively in an oxide; and for still others the highest oxidation states of oxides and fluorides are always equal.

<span class="mw-page-title-main">Difluorophosphate</span> Chemical compound

Difluorophosphate or difluorodioxophosphate or phosphorodifluoridate is an anion with formula PO
2
F
2
. It has a single negative charge and resembles perchlorate (ClO
4
) and monofluorosulfonate (SO3F) in shape and compounds. These ions are isoelectronic, along with tetrafluoroaluminate, phosphate, orthosilicate, and sulfate. It forms a series of compounds. The ion is toxic to mammals as it causes blockage to iodine uptake in the thyroid. However it is degraded in the body over several hours.

Silver(III) fluoride, AgF3, is an unstable, bright-red, diamagnetic compound containing silver in the unusual +3 oxidation state. Its crystal structure is very similar to that of gold(III) fluoride: it is a polymer consisting of rectangular AgF4 units linked into chains by fluoro bridges.

<span class="mw-page-title-main">Hexafluoroarsenate</span> Chemical compound

The hexafluoroarsenate anion is a chemical species with formula AsF−6. Hexafluoroarsenate is relatively inert, being the conjugate base of the notional superacid hexafluoroarsenic acid.

Gallium compounds are compounds containing the element gallium. These compounds are found primarily in the +3 oxidation state. The +1 oxidation state is also found in some compounds, although it is less common than it is for gallium's heavier congeners indium and thallium. For example, the very stable GaCl2 contains both gallium(I) and gallium(III) and can be formulated as GaIGaIIICl4; in contrast, the monochloride is unstable above 0 °C, disproportionating into elemental gallium and gallium(III) chloride. Compounds containing Ga–Ga bonds are true gallium(II) compounds, such as GaS (which can be formulated as Ga24+(S2−)2) and the dioxan complex Ga2Cl4(C4H8O2)2. There are also compounds of gallium with negative oxidation states, ranging from -5 to -1, most of these compounds being magnesium gallides (MgxGay).

References

  1. Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN   0-07-049439-8
  2. 1 2 3 NIOSH Pocket Guide to Chemical Hazards. "#0038". National Institute for Occupational Safety and Health (NIOSH).
  3. 1 2 3 4 Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN   978-0-08-037941-8.
  4. Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN   0-19-855370-6
  5. New alkali metal and tetramethylammonium tetrafluoroarsenates(III), their vibrational spectra and crystal structure of caesium tetrafluoroarsenate(III) Klampfer P, Benkič P, Lesar A, Volavšek B, Ponikvar M, Jesih A., Collect. Czech. Chem. Commun. 2004, 69, 339-350 doi : 10.1135/cccc20040339
  6. Alkali-metal heptafluorodiarsenates(III): their preparation and the crystal structure of the potassium salt, Edwards A.J., Patel S.N., J. Chem. Soc., Dalton Trans., 1980, 1630-1632, doi : 10.1039/DT9800001630
  7. Fluoride crystal structures. Part XV. Arsenic trifluoride–antimony pentafluoride, Edwards A. J., Sills R. J. C. J. Chem. Soc. A, 1971, 942 - 945, doi : 10.1039/J19710000942