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00:02:18 1 Characteristics
00:02:28 1.1 Electron configuration
00:02:57 1.2 Reactivity
00:03:31 1.3 Phases
00:06:11 1.4 Isotopes
00:07:25 2 Occurrence
00:08:35 2.1 Universe
00:08:44 2.2 Earth
00:09:44 3 History
00:11:38 3.1 Early discoveries
00:11:47 3.2 Isolation
00:13:18 3.3 Later uses
00:14:57 4 Compounds
00:16:25 4.1 Metals
00:16:56 4.2 Hydrogen
00:18:15 4.3 Other reactive nonmetals
00:19:00 4.4 Noble gases
00:20:45 4.5 Organic compounds
00:21:40 4.5.1 Discrete molecules
00:22:10 4.5.2 Polymers
00:23:18 5 Production
00:24:21 5.1 Industrial
00:24:30 5.2 Chemical
00:25:51 6 Industrial applications
00:26:59 6.1 Inorganic fluorides
00:29:39 6.2 Organic fluorides
00:30:49 6.2.1 Refrigerant gases
00:31:48 6.2.2 Polymers
00:33:03 6.2.3 Surfactants
00:35:18 6.2.4 Agrichemicals
00:36:03 7 Medicinal applications
00:37:15 7.1 Dental care
00:37:25 7.2 Pharmaceuticals
00:38:53 7.3 PET scanning
00:40:45 7.4 Oxygen carriers
00:41:20 8 Biological role
00:42:29 9 Toxicity
00:43:23 9.1 Hydrofluoric acid
00:44:06 9.2 Fluoride ion
00:45:45 10 Environmental concerns
00:47:32 10.1 Atmosphere
00:47:41 10.2 Biopersistence
00:49:20 11 See also
00:50:40 12 Notes
00:50:49 13 Sources
00:50:57 13.1 Citations
00:51:06 13.2 Indexed references
00:51:15 14 External links
00:51:24 External links



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"There is only one good, knowledge, and one evil, ignorance."
- Socrates



SUMMARY
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Fluorine is a chemical element with symbol F and atomic number 9. It is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive, as it reacts with almost all other elements, except for helium and neon.
Among the elements, fluorine ranks 24th in universal abundance and 13th in terrestrial abundance. Fluorite, the primary mineral source of fluorine which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb fluo meaning "flow" gave the mineral its name. Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its compounds, and several early experimenters died or sustained injuries from their attempts. Only in 1886 did French chemist Henri Moissan isolate elemental fluorine using low-temperature electrolysis, a process still employed for modern production. Industrial production of fluorine gas for uranium enrichment, its largest application, began during the Manhattan Project in World War II.
Owing to the expense of refining pure fluorine, most commercial applications use fluorine compounds, with about half of mined fluorite used in steelmaking. The rest of the fluorite is converted into corrosive hydrogen fluoride en route to various organic fluorides, or into cryolite, which plays a key role in aluminium refining. Organic fluorides have very high chemical and thermal stability; their major uses are as refrigerants, electrical insulation and cookware, the last as PTFE (Teflon). Pharmaceuticals such as atorvastatin and fluoxetine also contain fluorine, and the fluoride ion inhibits dental cavities, and so finds use in toothpaste and water fluoridation. Global fluorochemical sales amount to more than US$15 billion a year.
Fluorocarbon gases are generally greenhouse gases with global-warming potentials 100 to 20,000 times that of carbon dioxide. Organofluorine compounds persist in the environment due to the strength of the carbon–fluorine bond. Fluorine has no known metabolic role in mammals; a few plants synthesize organofluorine poisons that deter herbivores.

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