Chromium(IV) fluoride

Chromium(IV) fluoride is an inorganic compound with the chemical formula CrF₄. It has a dark greenish-black color when solid. It rapidly hydrolyzes in presence of moisture in air or directly in water.^[3]

Chromium(IV) fluoride

Names
IUPAC name Chromium(IV) fluoride
Other names Chromium fluoride, Chromium tetrafluoride
Identifiers
CAS Number	10049-11-3 Y
3D model (JSmol)	Interactive image
ChemSpider	52082975
PubChem CID	57346073
UNII	LXA70EM86D Y
CompTox Dashboard (EPA)	DTXSID90721095
InChI InChI=1S/Cr.4FH/h;4*1H/q+4;;;;/p-4 Key: SYJRAUIOIRVQSW-UHFFFAOYSA-J
SMILES [Cr+4].[F-].[F-].[F-].[F-]
Properties
Chemical formula	CrF4
Molar mass	127.9897 g·mol−1
Appearance	green crystals,[1] amorphous brown beads[2]
Density	2.89 g/cm3[1]
Melting point	277 °C (531 °F; 550 K)[1]
Boiling point	~ 400 °C (752 °F; 673 K)[2]
Solubility in water	reacts with water[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

Powdered chromium or CrCl₃ is exposed to fluorine gas at a temperature of 350-500 °C, which creates a mix of CrF₄ and CrF₅. The CrF₄ settles out as varnish-like brown beads upon cooling.^[2]

Reactions

Chromium(IV) fluoride is easily reduced.^[4]

It will react with water:

CrF₄ + 2H₂O → CrO₂ + 4HF