Potassium: potassium fluoride

potassium fluoride is known by the following synonyms:

  • potassium fluoride
  • potassium(I) fluoride

The oxidation number of potassium in potassium fluoride is 1.

  • Formula: KF
  • Hill system formula: F1K1
  • CAS registry number: [7789-23-3]
  • Formula weight: 58.097
  • Class: fluoride
  • Colour: white
  • Appearance: crystalline solid
  • Melting point: 858°C
  • Boiling point: 1502°C
  • Density: 2480 kg m-3

Synthesis

One way to make potassium fluoride is to react the hydroxide with hydrofluoric acid. The resulting salt can then be purified by recrystallization.

KOH(aq) + HF(aq) → KF(aq) + H2O(l)

While not a normal route of preparation because of the expense, potassium metal reacts vigorously with all the halogens to form potassium halides. So, it burns with fluorine, F2, to form potassium(I) fluoride, KF.

2K(s) + F2(g) → 2KF(s)

Solid state structure

  • Geometry of potassium: 6 coordinate: octahedral
  • Prototypical structure: NaCl (rock salt)

Crystal structure of potassium fluoride

Element analysis

Element percentages in potassium fluoride
Element %
F 32.70
K 67.30

Isotope pattern for KF

THe chart below shows the calculated isotope pattern for the formula KF with the most intense ion set to 100%.

Suppliers

Coming soon...

References

The data on these compounds pages are assembled and adapted from the primary literature and several other sources including the following.

  • R.T. Sanderson in Chemical Periodicity, Reinhold, New York, USA, 1960.
  • N.N. Greenwood and A. Earnshaw in Chemistry of the Elements, 2nd edition, Butterworth, UK, 1997.
  • F.A. Cotton, G. Wilkinson, C.A. Murillo, and M. Bochmann, in Advanced Inorganic Chemistry, John Wiley & Sons, 1999.
  • A.F. Trotman-Dickenson, (ed.) in Comprehensive Inorganic Chemistry, Pergamon, Oxford, UK, 1973.
  • R.W.G. Wyckoff, in Crystal Structures, volume 1, Interscience, John Wiley & Sons, 1963.
  • A.R.West in Basic solid state chemistry Chemistry, John Wiley & Sons, 1999.
  • A.F. Wells in Structural inorganic chemistry, 4th edition, Oxford, UK, 1975.
  • J.D.H. Donnay, (ed.) in Crystal data determinative tables, ACA monograph number 5, American Crystallographic Association, USA, 1963.
  • D.R. Lide, (ed.) in Chemical Rubber Company handbook of chemistry and physics, CRC Press, Boca Raton, Florida, USA, 77th edition, 1996.
  • J.W. Mellor in A comprehensive treatise on inorganic and theoretical chemistry, volumes 1-16, Longmans, London, UK, 1922-1937.
  • J.E. Macintyre (ed.) in Dictionary of inorganic compounds, volumes 1-3, Chapman & Hall, London, UK, 1992.

WebElements Shop

You can buy periodic table posters, mugs, T-shirts, fridge magnets, games, molecular models, and more at the WebElements shop