Mercury monofluoride

From Wikipedia, the free encyclopedia
  (Redirected from Mercury(I) fluoride)
Jump to: navigation, search
Mercury(I) fluoride
Mercury(I) fluoride
Identifiers
CAS number 13967-25-4
Properties
Molecular formula Hg2F2
Molar mass 439.177 g/mol
Appearance yellow cubic crystals
Density 8.73 g/cm³, solid
Solubility in water decomposes[1]
Hazards
EU classification Very toxic (T+)
Dangerous for
the environment (N)
R-phrases R26/27/28, R33, R50/53
S-phrases S13, S28, S45, S60, S61[2]
Flash point non-flammable
Related compounds
Other anions Mercury(I) chloride
Mercury(I) bromide
Mercury(I) iodide
Other cations Zinc fluoride
Cadmium fluoride
Mercury(II) fluoride
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Mercury(I) fluoride or mercurous fluoride is the chemical compound composed of mercury and fluorine with the formula Hg2F2. It consists of small yellow cubic crystals which turn black when exposed to light.[3]

Synthesis[edit]

Mercury(I) fluoride is prepared by the reaction of mercury(I) carbonate with hydrofluoric acid:

Hg2CO3 + 2 HF → Hg2F2 + CO2 + H2O

Reactions[edit]

When added to water, mercury(I) fluoride hydrolyzes to elemental liquid mercury, mercury(II) oxide, and hydrofluoric acid:[3]

Hg2F2 + H2O → Hg + HgO + 2 HF

It can be used in the Swarts reaction to convert alkyl halides into alkyl fluorides

[4]
2 R-X + Hg2F2 → 2 R-F + Hg2X2
where X = Cl, Br, I

Structure[edit]

In common with other Hg(I) (mercurous) compounds which contain linear X-Hg-Hg-X units, Hg2F2 contains linear FHg2F units with an Hg-Hg bond length of 251 pm (Hg-Hg in the metal is 300 pm) and an Hg-F bond length of 214 pm.[5] The overall coordination of each Hg atom is octahedral, as, in addition to the two nearest neighbours, there are four other F atoms at 272 pm.[5] The compound is often formulated as Hg22+ 2F.[6]

References[edit]

  1. ^ Perry, Dale L.; Phillips, Sidney L. (1995), Handbook of Inorganic Compounds, CRC Press, p. 256, ISBN 0-8493-8671-3, retrieved 2008-06-17 
  2. ^ 339318 Mercury(I) fluoride technical grade, Sigma-Aldrich, retrieved 2008-06-17 
  3. ^ a b Perry, Dale L.; Phillips, Sidney L. (1995), Handbook of Inorganic Compounds, CRC Press, p. 256, ISBN 0-8493-8671-3, retrieved 2008-06-17 
  4. ^ Beyer, Hans; Walter, Wolfgang; Lloyd, Douglas (1997), Organic Chemistry, Horwood Publishing, p. 136, ISBN 1-898563-37-3, retrieved 2008-06-17 
  5. ^ a b Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
  6. ^ Cotton, F. Albert; Wilkinson, Geoffrey; Murillo, Carlos A.; Bochmann, Manfred (1999), Advanced Inorganic Chemistry (6th ed.), New York: Wiley-Interscience, ISBN 0-471-19957-5