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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 .
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 ...
Roholm conducted laboratory studies, interviewed cryolite workers, visited factories, and documented the progression of fluorine poisoning in humans and animals from gastrointestinal upsets, neurological disorders, and bleeding gums to the advanced cases of skeletal fluorosis and crippling arthritis.
Fluorine is often added to drug molecules during drug design, as even a single atom can greatly change the chemical properties of the molecule in desirable ways. Because of the considerable stability of the carbon–fluorine bond , many drugs are fluorinated to delay their metabolism , which is the chemical process in which the drugs are turned ...
Its salts and minerals are important chemical reagents and industrial chemicals, mainly used in the production of hydrogen fluoride for fluorocarbons. Fluoride is classified as a weak base since it only partially associates in solution, but concentrated fluoride is corrosive and can attack the skin. Fluoride is the simplest fluorine anion.
In order to combat the potential global warming effects of F-gases, and as part of the EU's Kyoto protocol commitments, in 2006 the European Union passed two pieces of legislation controlling their use: the F-gas Regulation (EC) No 842/2006 and the Mobile Air Conditioning Directive Directive 2006/40/EC. The F-gas Regulation adopts an approach ...
At 400 ppb, fluorine is estimated to be the 24th most common element in the universe. It is comparably rare for a light element (elements tend to be more common the lighter they are). All of the elements from atomic number 6 (carbon) to atomic number 12 (magnesium) are hundreds or thousands of times more common than fluorine except for 11 (sodium).
Because the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each other, the methane-derived CFCs deviate from perfect tetrahedral symmetry. [5] The physical properties of CFCs and HCFCs are tunable by changes in the number and identity of the halogen atoms. In general, they are volatile but less so ...