Radon difluoride ( RnF 2 ) is a compound of radon , a radioactive noble gas . Radon reacts readily with fluorine to form a solid compound, but this decomposes on attempted vaporization and its exact composition is uncertain. Calculations suggest that it may be ionic , unlike all other known binary noble gas compounds . The usefulness of radon compounds is limited because of the radioactivity of radon. The longest-lived isotope , radon-222 , has a half-life of only 3.82 days, which decays by α-emission to yield polonium-218.
14-497: When radon is heated to 400 °C with fluorine, radon difluoride is formed. Radon difluoride can be reduced to radon and hydrogen fluoride when heated with hydrogen gas at 500 °C. This inorganic compound –related article is a stub . You can help Misplaced Pages by expanding it . Hydrogen fluoride 15 (in DMSO) Hydrogen fluoride (fluorane) is an inorganic compound with chemical formula H F . It
28-433: A component of superacids . Due to strong and extensive hydrogen bonding , it boils at near room temperature, which is much higher of a temperature than other hydrogen halides . Hydrogen fluoride is an extremely dangerous gas, forming corrosive and penetrating hydrofluoric acid upon contact with moisture . The gas can also cause blindness by rapid destruction of the corneas . In 1771 Carl Wilhelm Scheele prepared
42-514: A short covalent H–F bond of 95 pm length, are linked to neighboring molecules by intermolecular H–F distances of 155 pm. Liquid HF also consists of chains of HF molecules, but the chains are shorter, consisting on average of only five or six molecules. Hydrogen fluoride does not boil until 20 °C in contrast to the heavier hydrogen halides, which boil between −85 °C (−120 °F) and −35 °C (−30 °F). This hydrogen bonding between HF molecules gives rise to high viscosity in
56-501: A weak acid, unlike the other hydrohalic acids, due to the formation of hydrogen-bonded ion pairs [ H 3 O ·F ]. However concentrated solutions are strong acids, because bifluoride anions are predominant, instead of ion pairs. In liquid anhydrous HF, self-ionization occurs: which forms an extremely acidic liquid ( H 0 = −15.1 ). Like water, HF can act as a weak base, reacting with Lewis acids to give superacids . A Hammett acidity function ( H 0 ) of −21
70-411: Is a very poisonous, colorless gas or liquid that dissolves in water to yield hydrofluoric acid . It is the principal industrial source of fluorine , often in the form of hydrofluoric acid, and is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers such as polytetrafluoroethylene (PTFE). HF is also widely used in the petrochemical industry as
84-447: Is fluorinated by HF to produce chlorodifluoromethane (R-22): Pyrolysis of chlorodifluoromethane (at 550-750 °C) yields TFE. HF is a reactive solvent in the electrochemical fluorination of organic compounds. In this approach, HF is oxidized in the presence of a hydrocarbon and the fluorine replaces C–H bonds with C–F bonds . Perfluorinated carboxylic acids and sulfonic acids are produced in this way. 1,1-Difluoroethane
98-424: Is highly corrosive and a powerful contact poison. Exposure requires immediate medical attention. It can cause blindness by rapid destruction of the corneas . Breathing in hydrogen fluoride at high levels or in combination with skin contact can cause death from an irregular heartbeat or from pulmonary edema (fluid buildup in the lungs). Fluoroantimonic acid Too Many Requests If you report this error to
112-407: Is more common industrially than its aqueous solution, hydrofluoric acid . Its main uses, on a tonnage basis, are as a precursor to organofluorine compounds and a precursor to cryolite for the electrolysis of aluminium. HF reacts with chlorocarbons to give fluorocarbons. An important application of this reaction is the production of tetrafluoroethylene (TFE), precursor to Teflon . Chloroform
126-438: Is obtained with antimony pentafluoride (SbF 5 ), forming fluoroantimonic acid . Hydrogen fluoride is typically produced by the reaction between sulfuric acid and pure grades of the mineral fluorite : About 20% of manufactured HF is a byproduct of fertilizer production, which generates hexafluorosilicic acid . This acid can be degraded to release HF thermally and by hydrolysis: In general, anhydrous hydrogen fluoride
140-449: Is produced by adding HF to acetylene using mercury as a catalyst. The intermediate in this process is vinyl fluoride or fluoroethylene, the monomeric precursor to polyvinyl fluoride . The electrowinning of aluminium relies on the electrolysis of aluminium fluoride in molten cryolite. Several kilograms of HF are consumed per ton of Al produced. Other metal fluorides are produced using HF, including uranium tetrafluoride . HF
154-418: Is the precursor to elemental fluorine , F 2 , by electrolysis of a solution of HF and potassium bifluoride . The potassium bifluoride is needed because anhydrous HF does not conduct electricity. Several thousand tons of F 2 are produced annually. HF serves as a catalyst in alkylation processes in refineries. It is used in the majority of the installed linear alkyl benzene production facilities in
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#1732783423944168-484: The aqueous solution, hydrofluoric acid in large quantities, although hydrofluoric acid had been known in the glass industry before then. French chemist Edmond Frémy (1814–1894) is credited with discovering hydrogen fluoride (HF) while trying to isolate fluorine . HF is diatomic in the gas-phase. As a liquid, HF forms relatively strong hydrogen bonds , hence its relatively high boiling point. Solid HF consists of zig-zag chains of HF molecules. The HF molecules, with
182-475: The liquid phase and lower than expected pressure in the gas phase. HF is miscible with water (dissolves in any proportion). In contrast, the other hydrogen halides exhibit limiting solubilities in water. Hydrogen fluoride forms a monohydrate HF H 2 O with melting point −40 °C (−40 °F), which is 44 °C (79 °F) above the melting point of pure HF. Aqueous solutions of HF are called hydrofluoric acid . When dilute, hydrofluoric acid behaves like
196-671: The world. The process involves dehydrogenation of n -paraffins to olefins, and subsequent reaction with benzene using HF as catalyst. For example, in oil refineries "alkylate", a component of high- octane petrol ( gasoline ), is generated in alkylation units, which combine C 3 and C 4 olefins and iso -butane . Hydrogen fluoride is an excellent solvent. Reflecting the ability of HF to participate in hydrogen bonding, even proteins and carbohydrates dissolve in HF and can be recovered from it. In contrast, most non-fluoride inorganic chemicals react with HF rather than dissolving. Hydrogen fluoride
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