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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.
Substituting a fluorine into a para position, however, protects the aromatic ring and prevents the epoxide from being produced. [13] Adding fluorine to biologically active organic compounds increases their lipophilicity (ability to dissolve in fats), because the carbon–fluorine bond is even more hydrophobic than the carbon–hydrogen bond.
Moissan's fluorine cell, from his 1887 publication. Fluorine is a relatively new element in human applications. In ancient times, only minor uses of fluorine-containing minerals existed. The industrial use of fluorite, fluorine's source mineral, was first described by early scientist Georgius Agricola in the 16th century, in the context of ...
Fluoride, the chemical ion of the mineral fluorine, is naturally present in trace amounts, according to the Centers for Disease Control and Prevention, in soil, water, plants, and some food ...
fluorine: 9: 3a: Affects bone density in humans; creates fluoroapatite, which makes tooth enamel hard and relatively impervious to chemical action, compared to bone. [11] Improves growth in rats; has pharmacologic effects – helps to treat other deficiencies, e.g. of iron. Absence of fluorine has no clear adverse consequences in animals. [21]
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 ...
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 ]
The researchers discovered that all of the 13 bands that advertised that they were made from fluoroelastomers contained fluorine, which indicates the potential presence of PFAS. Two of the nine ...