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Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen [note 1] and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases. It is highly toxic.
PET scan using fluorine-18. Fluorine may interact with biological systems in the form of fluorine-containing compounds. Though elemental fluorine (F 2) is very rare in everyday life, fluorine-containing compounds such as fluorite occur naturally as minerals. Naturally occurring organofluorine compounds are extremely rare. Man-made fluoride ...
The fluorine–fluorine bond of the difluorine molecule is relatively weak when compared to the bonds of heavier dihalogen molecules. The bond energy is significantly weaker than those of Cl 2 or Br 2 molecules and similar to the easily cleaved oxygen–oxygen bonds of peroxides or nitrogen–nitrogen bonds of hydrazines. [8]
Fluorine is an important element for biological systems. From a mammalian health perspective, it is notable as a component of fluorapatite , a key mineral in the teeth of humans that have been exposed to fluorine, as well as shark and fish teeth. [ 4 ]
And any created fluorine within stars is rapidly eliminated through strong nuclear fusion reactions—either with hydrogen to form oxygen and helium, or with helium to make neon and hydrogen. [ 2 ] [ 3 ] The presence of fluorine at all—outside of temporary existence in stars—is somewhat of a mystery because of the need to escape these ...
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
Fluorine has the lowest polarizability of all atoms: 0.56 10 −24 cm 3. [1] This causes very weak dispersion forces between polyfluorinated molecules and is the reason for the often-observed boiling point reduction on fluorination as well as for the simultaneous hydrophobicity and lipophobicity of polyfluorinated compounds whereas other ...
Charles Betts, a prominent anti-fluoridationist, charged that fluoridation was "better than using the atom bomb because the atom bomb has to be made, has to be transported to the place it is to be set off while poisonous fluorine has been placed right beside the water supplies by the Americans themselves ready to be dumped into the water mains ...