fluoride, KHF sub 2 sub , and ammonium bifluoride NH sub 4 sub HF sub 2 sub . Many salts claimed to be anhydrous sources of fluoride e.g. tetra n butylammonium fluoride can decompose yielding bifluoride. Autodissociation of pure HF The bifluoride ion also contributes to the unusually high auto protolysis ... math H sub 2 sub F sup sup sub HF sub HF sub 2 sub sup sup sub HF sub See also Ammonium bifluoride Potassium bifluoride References commonscat bifluoride ion reflist Category Anions Category Fluorides fr Bifluorure it Idrogenodifluoruro nl Bifluoride ja zh ... more details
chembox verifiedrevid 399900008 Name Potassium bifluoride ImageFile ImageName IUPACName Potassium bifluoride OtherNames Potassium hydrogen difluoride Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 21241938 InChI 1 F2H.K c1 2 h1H q 1 1 InChIKey NABAXLWFTDYCFT UHFFFAOYAS SMILES K .F F StdInChI Ref stdinchicite correct chemspider StdInChI 1S F2H.K c1 2 h1H q 1 1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey NABAXLWFTDYCFT UHFFFAOYSA N CASNo 7789 29 9 PubChem 11829350 RTECS TS6650000 Section2 Chembox Properties Formula HF sub 2 sub K MolarMass 78.103 g mol Appearance colourless solid Density 2.37 g cm sup 3 sup Solubility MeltingPt 239 C BoilingPt decomp. Section3 Chembox Structure Coordination CrystalStruct monoclinic Section7 Chembox Hazards ExternalMSDS EUClass Toxic T , Corrosive C RPhrases R25 34 SPhrases S22 26, S37 45 FlashPt non flammable Section8 Chembox Related OtherAnions Potassium fluoride OtherCations Sodium bifluoride, ammonium bifluoride Potassium bifluoride is the inorganic compound with the chemical formula formula KHF sub 2 sub . This colourless salt consists of the potassium cation and the bifluoride HF sub 2 sub sup &minus sup anion. The salt is used in etchant for glass. Sodium bifluoride is related and is also of commercial use as an etchant as well as in cleaning products. ref name Aigueperse Jean Aigueperse, Paul Mollard, Didier Devilliers, Marius Chemla, Robert Faron, Ren e Romano, Jean Pierre Cuer, Fluorine Compounds, Inorganic in Ullmann s Encyclopedia of Industrial Chemistry 2005 Wiley VCH, Weinheim. DOI 10.1002 14356007.a11 307 ref Nature of the chemical bond in the bifluoride anion Potassium bifluoride, as its name indicates, contains a bifluoride , or hydrogen difluoride anion HF sub 2 ..., for the first time, hydrogen fluoride . Potassium bifluoride is prepared by treating potassium ... sub F sub 3 sub . ref name Aigueperse See also Ammonium bifluorideBifluorideBifluoride anion References ... more details
ammonium NH sub 4 sub sup sup cation tetrahedral br bifluoride HF sub 2 sub sup sup anion ... Autoignition ExploLimits LD50 PEL Section8 Chembox Related OtherCations potassium bifluoride ... route to hydrofluoric acid . Structure Ammonium bifluoride, as its name indicates, contains a bifluoride ... atoms. Solutions contain tetrahedral ammonium NH sub 4 sub sup sup cations and linear bifluoride HF sub 2 sub sup sup anions. Production and applications Ammonium bifluoride is a component of some ... O Potassium bifluoride is a related more commonly used etchant. Ammonium bifluoride has been considered ... the bifluoride H sub 2 sub SiF sub 6 sub 6 ammonia NH sub 3 sub 2 H sub 2 sub O SiO sub 2 sub 6 NH sub 4 sub F 2 NH sub 4 sub F NH sub 3 sub NH sub 4 sub HF sub 2 sub The resulting ammonium bifluoride is converted to the sodium bifluoride, which thermally decomposes to release HF. ref name Aigueperse ... VCH, Weinheim. DOI 10.1002 14356007.a11 307 ref See also BifluorideBifluoride anion Potassium bifluoride References references A. F. Wells 1984 Structural Inorganic Chemistry , 5th ed., Oxford ... more details
Unreferenced date December 2009 A symmetric hydrogen bond is a special type of hydrogen bond in which the proton is spaced exactly halfway between two identical atoms. The strength of the bond to each of those atoms is equal. It is an example of a 3 center 4 electron bond . This type of bond is much stronger than normal hydrogen bonds, in fact, its strength is comparable to a covalent bond . It is seen in ice at high pressure Ice X , and also in the solid phase of many anhydrous acids such as hydrofluoric acid and formic acid at high pressure. It is also seen in the bifluoride ion F H F sup sup . Much has been done to explain the symmetric hydrogen bond quantum mechanically, as it seems to violate the octet rule duet rule for the first shell The proton is effectively surrounded by four electron s. Because of this problem, some consider it to be an ionic bond . Chemical bonds DEFAULTSORT Symmetric Hydrogen Bond Category Chemical bonding ... more details
chembox verifiedrevid 402557857 ImageFile Potassium fluoride 3D ionic.png ImageSize IUPACName Potassium fluoride OtherNames Section1 Chembox Identifiers Abbreviations ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 23006 UNII Ref fdacite correct FDA UNII 9082WG1G3F InChI 1S FH.K h1H q 1 p 1 InChIKey NROKBHXJSPEDAR REWHXWOFAI SMILES F . K StdInChI Ref stdinchicite correct chemspider StdInChI 1S FH.K h1H q 1 p 1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey NROKBHXJSPEDAR UHFFFAOYSA M InChIKey1 NROKBHXJSPEDAR UHFFFAOYSA M CASNo 7789 23 3 CASNo Ref cascite correct CAS PubChem 522689 EINECS 232 151 5 InChI RTECS TT0700000 Section2 Chembox Properties Formula KF MolarMass 58.0967 g mol Appearance colourless crystals Density 2.48 g cm sup 3 sup MeltingPt 858 C BoilingPt 1505 C Solubility 92 g 100 mL 18 C SolubleOther soluble in hydrogen fluoride HF br insoluble in alcohol pKa Section7 Chembox Hazards EUClass Toxic T EUIndex 009 005 00 2 NFPA H 3 NFPA F 0 NFPA R 1 NFPA O RPhrases R23 24 25 SPhrases S1 2 , S26 , S45 FlashPt Non flammable PEL LD50 245 mg kg oral, guinea pig Section8 Chembox Related OtherAnions Potassium chloride br Potassium bromide br Potassium iodide OtherCations Lithium fluoride br Sodium fluoride br Rubidium fluoride br Caesium fluoride Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride , KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. It is an alkali metal halide and occurs naturally as the rare mineral carobbiite . Aqueous solutions of KF will etch glass due to the formation of soluble fluorosilicates, although Hydrofluoric acid HF is more effective. Preparation Potassium fluoride is prepared by dissolving potassium carbonate in excess hydrofluoric acid . Evaporation of the solution forms crystals of potassium bifluoride . The bifluoride on heating yields potassium fluoride K sub 2 sub CO sub 3 sub 4HF 2KHF sub 2 sub CO sub 2 sub H sub 2 ... more details
The 3 center 4 electron bond is a model used to explain bonding in hypervalent molecule s such as phosphorus pentafluoride , sulfur hexafluoride , the xenon fluorides , and the bifluoride ion. ref Greenwood&Earnshaw p. 897. ref ref Weinhold, F. Landis, C. Valency and bonding , Cambridge, 2005 pp. 275 306. ref It is also known as the Pimentel Rundle three center model after the work published by George C. Pimentel in 1951, ref Pimentel, G. C. The Bonding of Trihalide and Bifluoride Ions by the Molecular Orbital Method. J. Chem. Phys. 1951 , 19 , 446 448. doi 10.1063 1.1748245 ref which built on concepts developed earlier by Robert E. Rundle for electron deficient bonding. ref Rundle, R. E. Electron Deficient Compounds. II. Relative Energies of Half Bonds . J. Chem. Phys 1949 , 17 , 671 675. doi 10.1063 1.1747367 ref The model considers bonding of three colinear atoms. For example in XeF sub 2 sub , the linear F Xe F subunit is described by a set of three molecular orbitals MOs derived from colinear p orbitals on each atom. The Xe F bonds result from the combination of a filled p orbital in the central atom Xe with two half filled p orbitals on the axial atoms F , resulting in a filled bonding orbital, a filled non bonding orbital, and an empty antibonding orbital. The two lower energy MO s are doubly occupied. The HOMO is localized on the two terminal atoms. This localization of charge is accommodated by the fact that the terminal ligands are highly electronegative in hypervalent molecules. The molecules PF sub 5 sub and SF sub 4 sub are described, according to this model, as having one 3 center 4 electron bond as well as three and two other more conventionally described bonds, respectively. In SF sub 6 sub and in the xenon fluorides, all bonds are described with the 3 center 4 electron model. Image XeF2.png 400px thumb center Bonding in the hypervalent molecule XeF sub 2 sub according to the 3 center 4 electron bond model. The bonding in XeF sub 2 sub can also be sh ... more details
chembox ImageFile ScF3structure.jpg ImageName IUPACName Scandium III fluoride OtherNames Scandium trifluoride Section1 Chembox Identifiers CASNo 13709 47 2 PubChem 83678 RTECS VQ8930000 SMILES Section2 Chembox Properties Formula ScF sub 3 sub MolarMass 101.95112 g mol Appearance bright white powder Density 2.53 g cm sup 3 sup Solvent SolubleOther MeltingPt 1552 C ref name Wiberg&Holleman Egon Wiberg, Arnold Frederick Holleman 2001 Inorganic Chemistry , Elsevier ISBN 0123526515 ref BoilingPt 1607 C ref name Wiberg&Holleman Viscosity Section3 Chembox Structure CrystalStruct Rhombohedral , Pearson symbol R32 SpaceGroup hR12, No. 155 Section7 Chembox Hazards NFPA H 2 NFPA F 0 NFPA R 0 NFPA O Section8 Chembox Related OtherCpds Scandium III chloride br Scandium III nitrate Scandium III fluoride , ScF sub 3 sub , is an ionic compound. It has the vanadium III fluoride , VF sub 3 sub , structure, which is similar to the rhenium IV oxide , ReO sub 3 sub structure, containing 6 coordinate metal ions. ref name Wiberg&Holleman It is slightly soluble in water but dissolves in the presence of excess fluoride to form ScF sub 6 sub sup 3 sup . ref name Wiberg&Holleman ScF sub 3 sub can be produced by reacting scandium and fluorine. ref name Simon Cotton S.A.Cotton, Scandium, Yttrium and the Lanthanides Inorganic and Coordination Chemistry, Encyclopedia of Inorganic Chemistry, 1994, John Wiley & Sons, ISBN 0471936200 ref It is also formed during the extraction from the ore thortveitite by the reaction of Sc sub 2 sub O sub 3 sub with ammonium bifluoride at high temperature ref name Patnaik Pradyot Patnaik, 2003, Handbook of Inorganic Chemicals , McGraw Hill Professional, ISBN 0070494398 ref Sc sub 2 sub O sub 3 sub NH sub 4 sub HF sub 2 sub 2ScF sub 3 sub 6NH sub 4 sub F 3H sub 2 sub O The resulting mixture contains a number of metal fluorides and this is reduced by reaction with calcium metal at high temperature. ref name Patnaik Further purification steps are required to produce us ... more details
Orphan date January 2011 In chemistry , homoconjugation has two meanings, one in acid base chemistry and one in structural organic chemistry. Meaning in acid base chemistry Most commonly, the term refers to the enhancement of the acid dissociation constant acidity of an acid by itself. The effect is mainly observed at high concentrations. IUPAC recommends the term homoassociation , ref name IUPAC http goldbook.iupac.org H02842.html ref but this term has not gained wide usage. ref Agnes K tt, Ivo Leito, Ivari Kaljurand, Lilli Soov li, Vladislav M. Vlasov, Lev M. Yagupolskii, and Ilmar A. Koppel A Comprehensive Self Consistent Spectrophotometric Acidity Scale of Neutral Br nsted Acids in Acetonitrile J. Org. Chem., 2006, volume 71, pp 2829 2838. DOI 10.1021 jo060031y . ref The ionization of an acid varies nonlinearly with concentration. This effect arises from the stabilization of the conjugate base by its formation of a hydrogen bond to the parent acid. A well known case is hydrofluoric acid , which is a significantly stronger acid when concentrated than when dilute due to the following equilibria 2 HF H sup sup HF sub 2 sub sup sup The bifluoride anion HF sub 2 sub sup sup encourages the ionization of HF by stabilizing the F sup sup . Thus, the usual ionization constant for hydrofluoric acid 10 sup 3.15 sup understates the acidity of concentrated solutions of HF. Carboxylic acid s and phenol s also exhibit this effect. The effect of homoconjugation is often high in nonaqueous solutions, wherein dissociation is often low. Meaning in structural organic chemistry Homoconjugation also refers to orbital overlap of two systems separated by a non conjugating group, such as CH sub 2 sub . ref name IUPAC . For example, the molecule CH sub 2 sub CH CH sub 2 sub CH CH sub 2 sub 1,4 pentadiene is homoconjugated because the two C C double bond s which are systems because each double bond contains one bond are separated by of one CH sub 2 sub group. With this meaning, the n ... more details
chembox verifiedrevid 402870907 Name Vanadium III fluoride ImageFile Aluminium trifluoride 3D polyhedra.png ImageFile2 FeF3structure.jpg ImageName Vanadium III fluoride OtherNames Vanadium fluoride, Vanadium trifluoride Section1 Chembox Identifiers InChI 1 3FH.V h3 1H q 3 p 3 InChIKey PASVSMBJEYQYSN DFZHHIFOAM SMILES V 3 . F . F . F StdInChI Ref stdinchicite correct chemspider StdInChI 1S 3FH.V h3 1H q 3 p 3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey PASVSMBJEYQYSN UHFFFAOYSA K CASNo 10049 12 4 PubChem 66230 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 16057827 Section2 Chembox Properties Formula VF sub 3 sub MolarMass 107.9367 g mol Appearance gray green powder Density 3.363 g cm sup 3 sup , solid Solubility insoluble MeltingPt 1406 C BoilingPt Section3 Chembox Structure CrystalStruct Rhombohedral , Pearson symbol hR24 SpaceGroup R 3c, No. 167 Section7 Chembox Hazards EUClass not listed NFPA H 3 NFPA R 2 NFPA F 0 Section8 Chembox Related OtherAnions Vanadium III chloride br Vanadium III oxide br Vanadium III nitride OtherCations Vanadium IV fluoride OtherFunctn Function OtherCpds Vanadium III fluoride is the chemical compound with the formula Vanadium V Fluorine F sub 3 sub . This gray green, refractory solid is obtained in a two step procedure from V sub 2 sub O sub 3 sub . ref Sturm, B. J. Sheridan, C. W. Vanadium III Fluoride Inorganic Syntheses 1963 Vol. 7, pages 52 54. ISBN 0 88275 165 4. ref The first step entails conversion to the hexafluorovanadate III salt using ammonium bifluoride V sub 2 sub O sub 3 sub 6 NH sub 4 sub HF sub 2 sub 2 NH sub 4 sub sub 3 sub VF sub 6 sub 3 H sub 2 sub O In the second step, the hexafluorovanadate is thermally decomposed. NH sub 4 sub sub 3 sub VF sub 6 sub 3 NH sub 3 sub 3 hydrogen fluoride HF VF sub 3 sub The thermal decomposition of ammonium salts is a relatively common method for the preparation of inorganic solids. VF sub 3 sub can also be prepared by treatment of V sub 2 sub O sub 3 s ... more details
causes the ion pair to dissociate with formation of the hydrogen bonded bifluoride hydrogen difluoride ..., F sub 2 sub , is prepared by electrolysis of a solution of HF and potassium bifluoride . The potassium bifluoride is needed because anhydrous hydrogen fluoride does not conduct electricity. Several ... more details
chembox verifiedrevid 399885913 Name Ammonium fluoride ImageFileL1 Ammonium.svg ImageSizeL1 90px ImageNameL1 The ammonium cation ImageFileR1 F .svg ImageSizeR1 30px ImageNameR1 The fluoride anion ImageFile2 Ammonium fluoride 3D balls ionic.png ImageSize2 150px ImageName2 ball and stick model of an ammonium cation left and an fluoride anion right ImageFile3 Fluorid amonn .PNG ImageName3 Solid sample of ammonium fluoride IUPACName Ammonium fluoride OtherNames Neutral ammonium fluoride Section1 Chembox Identifiers InChI 1 FH.H3N h1H 1H3 SMILES F . NH4 InChIKey LDDQLRUQCUTJBB UHFFFAOYAM StdInChI Ref stdinchicite correct chemspider StdInChI 1S FH.H3N h1H 1H3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey LDDQLRUQCUTJBB UHFFFAOYSA N CASNo 12125 01 8 CASNo Ref cascite correct CAS RTECS BQ6300000 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 23806 EINECS 235 185 9 UNNumber 2505 Section2 Chembox Properties Formula NH sub 4 sub F MolarMass 37.037 g mol Appearance White crystalline solid br hygroscopic Density 1.009 g cm sup 3 sup Solubility 45.3 g 100 ml 25 C SolubleOther slightly soluble in alcohol, insoluble in liquid ammonia MeltingPt 100 C decomp Section3 Chembox Structure CrystalStruct Wurtzite crystal structure Wurtzite structure hexagonal Section7 Chembox Hazards ExternalMSDS http www.ilo.org public english protection safework cis products icsc dtasht icsc12 icsc1223.htm ICSC 1223 EUIndex 009 006 00 8 EUClass Toxic T RPhrases R23 24 25 SPhrases S1 2 , S26 , S45 NFPA H 3 NFPA F 0 NFPA R 0 NFPA O FlashPt Non flammable Section8 Chembox Related OtherAnions Ammonium chloride br Ammonium bromide br Ammonium iodide OtherCations Sodium fluoride br Potassium fluoride OtherCpds Ammonium bifluoride Ammonium fluoride is the inorganic compound with the formula NH sub 4 sub F. It crystallizes as small colourless prisms, having a sharp saline taste, and is exceedingly soluble in water. Reactions Ammonium fluoride adopts the Wurtzite crystal structure wu ... more details
chembox verifiedrevid 400095374 Name Formyl fluoride ImageFileL1 Formyl fluoride 2D.png ImageNameL1 Formyl fluoride ImageFileR1 Formyl fluoride 3D vdW.png ImageNameR1 Formyl fluoride IUPACName Formyl fluoride OtherNames Formic acid fluoride Section1 Chembox Identifiers SMILES FC O ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 14424 PubChem 15153 InChI 1 CHFO c2 1 3 h1H InChIKey NHGVZTMBVDFPHJ UHFFFAOYAX StdInChI Ref stdinchicite correct chemspider StdInChI 1S CHFO c2 1 3 h1H StdInChIKey Ref stdinchicite correct chemspider StdInChIKey NHGVZTMBVDFPHJ UHFFFAOYSA N CASNo 1493 02 3 Section2 Chembox Properties Formula CHFO MolarMass 48.02 g mol Appearance Colourless gas Density Solubility decomposes Solvent other solvents SolubleOther chlorocarbons, br Freon s MeltingPt 142 C BoilingPt 29 C Section3 Chembox Structure Dipole 2.02 Debye D ref name LeB LeBlanc, Jr., O. H. Laurie, V. W. Gwinn, W. D. Microwave Spectrum, Structure, and Dipole Moment of Formyl Fluoride The Journal of Chemical Physics 1960, volume 33, pp. 598 600. ref Section7 Chembox Hazards ExternalMSDS MainHazards toxic Section8 Chembox Related OtherCpds Formic acid br Hydrogen fluoride br Carbonyl fluoride Formyl fluoride is the organic compound with the formula FC O H. Preparation FC O H was first reported in the 1934. ref Nesmejanow, A. N. Kahn, E. J. ber die unmittelbare Synthese von S ure fluoriden aus S uren und die Herstellung von Formylfluorid Chemische Berichte. 1934, volume 67, page 370 373. DOI 10.1002 cber.19340670303 ref Among the many preparations, a typical one involves the reaction of sodium formate with benzoyl fluoride generated in situ from Potassium bifluoride KHF sub 2 sub and benzoyl chloride ref name Olah Olah, G. A. Ohannesian, L. Arvanaghi, M, Formylating Agents Chemical Reviews, 1987, volume 87, pp 671 686. DOI 10.1021 cr00080a001 ref NaOC O H C sub 6 sub H sub 5 sub C O F &rarr FC O H C sub 6 sub H sub 5 sub CO sub 2 sub Na Structure The molecule is planar C O and ... more details
File Tetrafluoroammonium ion.png thumb 150px 2D model of the tetrafluoroammonium ion The tetrafluoroammonium ion cation is a positively charged polyatomic ion with chemical formula chem NF 4 . It is equivalent to the ammonium ion where the hydrogen atoms surrounding the central nitrogen atom have been replaced by fluorine . ref cite doi 10.1070 RC1985v054n05ABEH003068 ref The tetrafluoroammonium ion forms salt chemistry salts with a large variety of fluorine bearing anions. These include the bifluoride anion chem HF 2 , tetrafluorobromate chem BrF 4 , metal pentafluorides chem XF 5 where X is germanium Ge , tin Sn , or titanium Ti , hexafluorides chem XF 6 where X is phosphorus P , arsenic As , nickel Ni , ref cite doi 10.1021 ic50175a017 ref antimony Sb , bismuth Bi , or platinum Pt , heptafluorides chem XF 7 where X is tungsten W , uranium U , or xenon Xe , octafluorides chem XeF 8 2 , ref cite doi 10.1021 ic00142a001 ref various oxyfluorides chem XF 5 O where X is W or U chem link fluorosulfuric acid FSO 3 , chem BrF 4 O , and perchlorate chem ClO 4 . ref name karlchriste cite doi 10.1021 ic00231a038 ref The nitrate salt, chem NF 4 NO 3 , has also been made. ref name hoge cite doi 10.1016 S0022 1139 01 00415 8 ref Structure The geometry of the tetrafluoroammonium ion is tetrahedral molecular geometry tetrahedral , with an estimated nitrogen fluorine bond length of 124 Picometre pm . All fluorine atoms are in equivalent positions. ref name sykes1 Synthesis Tetrafluoroammonium salts are prepared by oxidising nitrogen trifluoride with fluorine in the presence of a strong Lewis acid which acts as a fluoride ion acceptor. The original synthesis by Tolberg, Rewick, Stringham, and Hill in 1966 employs antimony pentafluoride as the Lewis acid ref name sykes1 2 chem NF 3 chem F 2 2 chem SbF 5 2 chem NF 4 SbF 6 The hexafluoroarsenate salt was also prepared by a similar reaction with arsenic pentafluoride at 120 C ref name sykes1 2 chem NF 3 chem F 2 2 chem AsF 5 ... more details
with in situ generated bifluoride, leads to tetrafluorinated ether products. Direct reaction with bifluoride affords trifluoromethyl containing products. span style float right padding ... more details
The covalent radius of fluorine is a measure of the size of a fluorine atom it is approximated at about 60 picometre s. Since fluorine is a relatively small atom with a large electronegativity , its covalent radius is difficult to evaluate. The covalent radius is defined as half the bond lengths between two neutral atoms of the same kind connected with a single bond . By this definition, the covalent radius of F is 71 pm. However, the F F bond in F sub 2 sub is abnormally weak and long. Besides, almost all bonds to fluorine are highly polar because of its large electronegativity, so the use of a covalent radius to predict the length of such a bond is inadequate and the bond lengths calculated from these radii are almost always longer than the experimental values. Bonds to fluorine have considerable ionic character, a result of its small atomic radius and large electronegativity. Therefore, the bond length of F is influenced by its ionic radius , the size of ion s in an ionic crystal, which is about 133 pm for fluoride ions. The ionic radius of fluoride is much larger than its covalent radius. When F becomes F sup sup , it gains one electron but has the same number of protons, meaning the attraction of the protons to the electrons is weaker, and the radius is larger. Brockway The first attempt at trying to find the covalent radius of fluorine was in 1938, by Brockway. ref name Brockway cite journal last1 Brockway first1 L. O. journal Journal of the American Chemical Society volume 60 pages 1348 year 1938 doi 10.1021 ja01273a021 ref Brockway prepared a vapour of F sub 2 sub molecules by means of the electrolysis of potassium bifluoride KHF sub 2 sub in a fluorine generator, which was constructed of Monel metal. Then, the product was passed over potassium fluoride so as to remove any hydrogen fluoride HF and to condense the product into a liquid . A sample was collected by evaporating the condensed liquid into a Pyrex flask. Finally, using electron diffractio ... more details
Infobox disease Name Skeletal fluorosis ICD10 ICD10 M 85 1 m 80 ICD9 ICD9 733.9 Skeletal fluorosis is a bone disease caused by excessive consumption of fluoride . In advanced cases, skeletal fluorosis causes pain and damage to bones and joints. Fluorine Forms Fluorine can be isolated in two different forms including the molecular, diatomic gas, F2, and the ionic form, F . It is very difficult to isolate Fluorine in its atomic form due to its high reactivity and electronegativity . Reactivity Fluorine is the most reactive of the halogens . Fluorine is the most electronegative element currently known. This means the elemental form, F, will actively seek another electron to satisfy the octet rule 8 electrons in the outer s and p shells . This extra electron could come from anything. Because of this, Fluorine is the strongest known oxidizer . It is only found naturally on earth as 19F, its only stable isotope . Aqueous HF Hydrofluoric acid , is weak acidic. This acid will dissociate in water, but only to small extent. In its dissociated form, F , it is a fairly strong base. Anhydrous HF hydrogen fluoride is a strong acid and its strength can be greatly increased through the addition a lewis acid such as antimony pentafluoride. Synthesis Fluorine is not produced in a monatomic, uncharged form. It is generally always manufactured from the mineral Fluorite , which is the major source of Fluorine on earth. Though it is not produced as an elemental form, Fluorine can be produced in its ionic and diatomic gas forms. This is done by a method developed by Henri Moissan in 1886. The method begins by reacting Potassium Fluoride and Hydrogen Fluoride, KF and HF respectively, to form Potassium Bifluoride , KHF2. This produce is produced in an aqueous solution and is further electrolyzed to form gaseous Hydrogen, gaseous Fluorine, and ionic Fluorine in an aqueous solution, H2, F2, and F respectively. Reactions Molecular Fluorine will act as an oxidant in most reactions. In electroch ... more details
the electrolysis of a solution of potassium bifluoride in hydrogen fluoride. Hydrogen fluoride required ... tonnes of fluorine are produced annually. Potassium bifluoride forms spontaneously from potassium ... Potassium bifluoride increases the electrical conductivity of the solution and provides the bifluoride anion in potassium bifluoride, the anion is whole HF2 that is oxidized to form fluorine at the anode ... of fluoride anion, many alkali metal fluorides form bifluoride s with the formula MHF sub 2 ... more details
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