Fluorine is a chemical element wi seembol F an atomic nummer 9. It is the lichtest halogen an exists as a heichly toxic pale yellae diatomic gas at staundary condeetions. As the maist electronegative element, it is extremely reactive: awmaist aw ither elements, includin some noble gases, form compoonds wi fluorine.

Fluorine, 9F
Template:Infobox element/symbol-to-top-image/alt
Liquid fluorine (at extremely law temperaturs)
Appearancegas: vera fauch yellae
liquid: bricht yellae
solid: skyre (beta), opaque (alpha)
Standard atomic weight Ar, std(F)18.998403163(6)[1]
Mass numberF:
Fluorine in the periodic cairt
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium


Atomic nummer (Z)9
Groupgroup 17 (halogens)
Periodperiod 2
Element category  Reactive nonmetal
Electron confeeguration[He] 2s2 2p5[2]
Electrons per shell2, 7
Pheesical properties
Phase at STPgas
Meltin pynt53.48 K ​(−219.67 °C, ​−363.41[3] °F)
Bylin pynt85.03 K ​(−188.11 °C, ​−306.60[3] °F)
Density (at STP)1.696[4] g/L
whan liquid (at b.p.)1.505[5] g/cm3
Treeple pynt53.48 K, ​90[3] kPa
Creetical pynt144.41 K, 5.1724[3] MPa
Heat o vapourisation6.51[4] kJ/mol
Molar heat capacity(Cp) (21.1 °C) 31[5] J·mol−1·K−1
(Cv) (21.1 °C) 23[5] J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 38 44 50 58 69 85
Atomic properties
Oxidation states−1 (oxidizes oxygen)
ElectronegativityPauling scale: 3.98[6]
Ionisation energies
Covalent radius64[7] pm
Van der Waals radius135[8] pm
Colour lines in a spectral range
Spectral lines o fluorine
Ither properties
Naitural occurrenceF: Primordial
Creestal structurbase-centred monoclinic
Monoclinic base-centered creestal structur for fluorine

alpha state (low-temperature)[9]
Thermal conductivity0.02591[10] W/(m·K)
Magnetic orderindiamagnetic, −1.2×10−4 (SI)[11][12]
CAS Nummer7782-41-4[6]
Naminefter the mineral fluorite, itsel named efter Latin fluo (taur pirr, in smeltin)
DiskiveryAndré-Marie Ampère (1810)
First isolationHenri Moissan[6] (Juin 26, 1886)
Named byHumphry Davy
Main isotopes o fluorine
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
18F trace 109.77 min β+ (96.9%) 18O
ε (3.1%) 18O
19F 100% stable
| references

Amang the elements, fluorine ranks 24t in universal abundance an 13t in terrestrial abundance. Fluorite, the primar mineral soorce o fluorine which gae the element its name, wis first descrived in 1529; as it wis addit tae metal ures tae lawer thair meltin pynts for smeltin, the Laitin verb fluo meanin "flowe" gae the mineral its name. Proponed as an element in 1810, fluorine pruived difficult an dangerous tae separate frae its compoonds, an several early experimenters dee'd or susteened injuries frae thair attempts. Anerly in 1886 did French chemist Henri Moissan isolate elemental fluorine uisin law-temperatur electrolysis, a process still employed for modren production. Industrial production o fluorine gas for uranium enrichment, its lairgest application, began in the Manhattan Project in Warld War II.

Awin tae the expense o refinin pure fluorine, maist commercial applications uise fluorine compoonds, wi aboot hauf o mined fluorite uised in steelmakkin. The rest o the fluorite is convertit intae corrosive hydrogen fluoride en route tae various organic fluorides, or intae cryolite which plays a key role in aluminium refinin. Organic fluorides hae very heich chemical an thermal stability; thair major uises are as refrigerants, electrical insulation an cuikware, the last as PTFE (Teflon). Pharmaceuticals sic as atorvastatin an fluoxetine an aa contain fluorine, an the fluoride ion inhibits dental cavities, an sae finds uise in toothpaste an watter fluoridation. Global fluorochemical sales amount tae mair nor US$15 billion a year.

Fluorocarbon gases are generally greenhoose gases wi global-wairmin potentials 100 tae 20,000 times that o carbon dioxide. Organofluorine compoonds persist in the environment due tae the strenth o the carbon–fluorine bond. Fluorine haes na kent metabolic role in mammals; a few plants synthesize organofluorine pushions that deter yerbivores.


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  2. Jaccaud et al. 2000, p. 381.
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  10. Yaws & Braker 2001, p. 385.
  11. Mackay, Mackay & Henderson 2002, p. 72.
  12. Cheng, H.; Fowler, D. E.; Henderson, P. B.; Hobbs, J. P.; Pascaloni, M. R. (1999). "On the magnetic susceptibility of fluorine". Journal of Physical Chemistry A. 103 (15): 2861–2866. doi:10.1021/jp9844720.
  13. Chiste, V.; Be, M. M. (2006). "F-18" (PDF). Table de radionucleides. Laboratoire National Henri Becquerel. Retrieved 15 Juin 2011.
  14. 14.0 14.1 14.2 Dean 1999, p. 4.6.