The fluorinated antiinflammatories dexamethasone and triamcinolone are among the most potent of the synthetic corticosteroids class of drugs.
Many important agents for general anesthesia such as sevoflurane, desflurane, and isoflurane are hydrofluorocarbon derivatives.These compounds are also added to municipal water supplies, a process called water fluoridation, though a number of health concerns has sometimes led to controversy. Compounds of fluorine, including sodium fluoride (NaF), stannous fluoride (SnF 2) and sodium MFP, are used in toothpaste to prevent dental cavities.Compounds of fluorine such as fluoropolymers, potassium fluoride and cryolite are utilized in applications such as anti-reflective coatings and dichroic mirrors on account of their unusually low refractive index.Polytetrafluoroethylene, also known as the non-stick Teflon surface in baking pans.The experiments failed because fluorine proved difficult to handle, and its combustion products proved extremely toxic and corrosive. Some researchers including US space scientists in the early 1960s have studied elemental fluorine gas as a possible rocket propellant due to its exceptionally high specific impulse.Fluorides have been used in the past to help molten metal flow, hence the name.In much higher concentrations, sodium fluoride has been used as an insecticide, especially against cockroaches.Sodium hexafluoroaluminate ( cryolite), is used in the electrolysis of aluminium.It does not occur in nature, so it is a useful tracer gas, though as an exceptionally potent greenhouse gas its use in unenclosed systems is inadvisable. Sulfur hexafluoride is an extremely inert and nontoxic gas, very useful as an insulator in high-voltage electrical equipment.Hydrofluorocarbons do have a greenhouse effect, but a small one compared with carbon dioxide and methane. Interestingly, since it is chlorine and bromine radicals which harm the ozone layer, not fluorine, compounds which do not contain chlorine or bromine but contain only fluorine, carbon and hydrogen (called hydrofluorocarbons) are not on the EPA list of ozone-depleting substances, and have been widely used as replacements for the chlorine- and bromine-containing fluorocarbons. Chlorofluorocarbons have been banned for these applications because they contribute to ozone destruction and the ozone hole. Fluorochlorohydrocarbons are used extensively in air conditioning and in refrigeration.Along with some of its compounds, fluorine is used in the production of pure uranium from uranium hexafluoride and in the synthesis of numerous commercial fluorochemicals, including vitally important pharmaceuticals, agrochemical compounds, lubricants, and textiles.Fluorine is indirectly used in the production of low friction plastics such as Teflon, and in halons such as freon.Hydrofluoric acid (chemical formula HF) is used to etch glass in light bulbs and other products.Xenon difluoride is also used for this last purpose. Atomic fluorine and molecular fluorine are used for plasma etching in semiconductor manufacturing, flat panel display production and MEMS (microelectromechanical systems) fabrication.Fluorine compounds with metals are among the most stable of salts. They often consist of crystalline ionic salts. Other forms are fluoro- complexes, such as −, or H 2F +.įluorides are compounds that combine fluorine with some positively charged counterpart. In aqueous solution, fluorine commonly occurs as the fluoride ion F −, although highly diluted HF is such a weak acid that substantial amounts of it are present in any water solution of fluoride at near neutral pH. In moist air it reacts with water to form also-dangerous hydrofluoric acid. It is far too reactive to be found in elemental form. It is so reactive that metals, and even water, as well as other substances, burn with a bright flame in a jet of fluorine gas. Even in dark, cool conditions, fluorine reacts explosively with hydrogen. Fluorine even combines with argon, krypton, xenon, and radon. It has an oxidation number -1, except when bonded to another fluorine in F 2 which gives it an oxidation number of 0. It is the most reactive and most electronegative of all the elements (4.0), and readily forms compounds with most other elements. Pure fluorine (F 2) is a corrosive pale yellow or brown gas that is a powerful oxidizing agent. Yellowish brown gas Standard atomic weight
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