NationMaster - Encyclopedia: Chlorine trifluoride

Chlorine trifluoride is the chemical compound with the formula ClF₃. This colourless, poisonous, corrosive and very reactive gas condenses to a pale-greenish yellow liquid, the form in which it is most often sold (pressurized at room temperature). The compound is primarily of interest as a component in rocket fuels, in industrial cleaning and etching operations primarily in the semiconductor industry^[1] ^[2], nuclear reactor fuel processing^[3] and other industrial operations.^[4] Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 atmosphere... In chemistry, the standard molar entropy is the entropy content of one mole of substance, under conditions of standard temperature and pressure. ... The examples and perspective in this article or section may not represent a worldwide view. ... NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. ... Image File history File links NFPA_704. ... Chlorine pentafluoride has formula ClF5. ... Chlorine monofluoride has formula ClF. External links National Pollutant Inventory - Flouride and compounds fact sheet WebBook page for ClF Categories: | | ... Supplementary data page Structure and properties n, Îµr, etc. ... The plimsoll symbol as used in shipping In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals exactly). ... Look up chemical compound in Wiktionary, the free dictionary. ... For other uses, see Gas (disambiguation). ...

Preparation, structure, and properties

It was first reported by Ruff and Krug who prepared it by fluorination of chlorine; this also produced ClF and the mixture was separated by distillation.^[5] General Name, symbol, number chlorine, Cl, 17 Chemical series nonmetals Group, period, block 17, 3, p Appearance yellowish green Standard atomic weight 35. ...

ClF₃ is approximately T-shaped. This structure is explicable in the context of VSEPR theory, which considers also lone pairs of electrons as occupying two equatorial positions of a hypothetic trigonal bipyramid. The elongated Cl-F_axial bonds are consistent with hypervalent bonding. Valence shell electron pair repulsion theory (VSEPR) (1957) is a model in chemistry that aims to generally represent the shapes of individual molecules [1] . To achieve this, it is necessary to construct a valid Lewis structure that shows all of the bonds within the molecule and the locations of lone...

Pure ClF₃ is stable to 180° in glass vessels, but above this temperature it decomposes by a free radical mechanism to the elements.
The main use of ClF₃ is to produce uranium hexafluoride, UF₆ as part of nuclear fuel processing and reprocessing, by the reaction: In chemistry free radicals are uncharged atomic or molecular species with unpaired electrons or an otherwise open shell configuration. ... Uranium hexafluoride (UF6), referred to as hex in industry, is a compound used in the uranium enrichment process that produces fuel for nuclear reactors and nuclear weapons. ...

Hazards

ClF₃ is a very strong oxidizing and fluorination agent. ClF₃ is extremely reactive with most inorganic and organic materials and will initiate the combustion of many materials without an ignition source and these reactions are often violent or in some cases explosive. Several metals give chlorides and fluorides, phosphorus yields PCl₃ plus PF₅, sulfur SCl₂ plus SF₄. ClF₃ is also violently water reactive in which it hydrolyses to a variety of hazardous chemicals such as hydrofluoric acid. H₂S explodes on being mixed with ClF₃ at room temperature. European Union Chemical hazard symbol for oxidizing agents Dangerous goods label for oxidizing agents Oxidizing agent placard An oxidizing agent (also called an oxidant or oxidizer) is A chemical compound that readily transfers oxygen atoms or A substance that gains electrons in a redox chemical reaction. ... The chloride ion is formed when the element chlorine picks up one electron to form an anion (negatively-charged ion) Clâˆ’. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. ... Fluoride is the ionic form of fluorine. ... General Name, symbol, number phosphorus, P, 15 Chemical series nonmetals Group, period, block 15, 3, p Appearance waxy white/ red/ black/ colorless Standard atomic weight 30. ... This article is about the chemical element. ... R-phrases , S-phrases , , , , Flash point nonflammable Related Compounds Other anions Hydrochloric acid Hydrobromic acid Hydroiodic acid Related compounds Hydrogen fluoride fluorosilicic acid Supplementary data page Structure and properties n, Îµr, etc. ... Hydrogen sulfide (or hydrogen sulphide) is the chemical compound with the formula H2S. This colorless, toxic and flammable gas is responsible for the foul odour of rotten eggs and flatulence. ...

The ability to surpass the oxidizing ability of oxygen leads to corrosivity against oxide-containing materials often thought as incombustible. In an industrial accident, a spill of 900 kg of chlorine trifluoride burned itself through 30 cm of concrete and 90 cm of gravel beneath.^[6] Any equipment that comes into contact with chlorine trifluoride must be carefully selected and cleaned, because any contamination can ignite on contact.

Exposure of larger amounts of chlorine trifluoride, as a liquid or as a gas, ignites tissue. The hydrolysis reaction with water is violent and exposure results in a thermal burn. The product of hydrolysis is hydrofluoric acid, which is corrosive to human tissue, absorbs through skin, selectively attacks bone and stimulates pain nerves, and causes a potentially lethal poisoning. R-phrases , S-phrases , , , , Flash point nonflammable Related Compounds Other anions Hydrochloric acid Hydrobromic acid Hydroiodic acid Related compounds Hydrogen fluoride fluorosilicic acid Supplementary data page Structure and properties n, Îµr, etc. ...

Military applications

Under the code name N-stoff ("substance N"), chlorine trifluoride was investigated for military applications by the Kaiser Wilhelm Institute in Nazi Germany from slightly before the start of World War II. Tests were made against mock-ups of the Maginot Line fortifications, and it was found to be an effective combined incendiary weapon and poison gas. From 1938 construction commenced on a partly bunkered, partly subterranean 31.76 km² munitions factory at Falkenhagen which was intended to produce 50 tonnes of N-stoff per month, plus Sarin. However by the time it was captured by the advancing Red Army in 1944, the factory had produced only about 30 to 50 tonnes, at a cost of over 100 German Reichsmark per kilogram^a. N-stoff was never used in war.^[7] A code name or cryptonym is a word or name used clandestinely to refer to another name or word. ... Kaiser Wilhelm Institute (in German Kaiser-Wilhelm-Gesellschaft) was the name of a number of scientific institutes in Germany before World War II. After 1945 they were re-organised and renamed as Max Planck Institutes. ... Nazi Germany, or the Third Reich, commonly refers to Germany in the years 1933–1945, when it was under the firm control of the totalitarian and fascist ideology of the Nazi Party, with the Führer Adolf Hitler as dictator. ... Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki TÅjÅ Casualties Military dead: 17,000,000 Civilian dead: 33,000... The Maginot Line (IPA: [maÊ’inoË], named after French minister of defense AndrÃ© Maginot) was a line of concrete fortifications, tank obstacles, artillery casemates, machine gun posts, and other defenses, which France constructed along its borders with Germany and Italy, in the light of experience from World War I... An incendiary device is a device or weapon designed to create a fire. ... Chemical warfare is warfare (and associated military operations) using the toxic properties of chemical substances to kill, injure or incapacitate an enemy. ... Year 1938 (MCMXXXVIII) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar. ... Bunkers in Albania A bunker is a defensive military fortification. ... This article is about the metric tonne. ... For other uses, see Sarin (disambiguation). ... For other organizations known as the Red Army, see Red Army (disambiguation). ... Year 1944 (MCMXLIV) was a leap year starting on Saturday (link will display full calendar) of the Gregorian calendar. ... User(s) Germany Subunit 1/100 Reichspfennig Symbol RM Reichspfennig Rpf. ... Kg redirects here. ...

Rocket propellant

Chlorine trifluoride has been investigated as a high-performance storable oxidizer in rocket propellant systems. Handling concerns, however, prevented its use. Clark summarized the difficulties, "It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively."^[8]^[9] Rocket propellants undergo exothermic chemical reactions which produce hot gas which is used by a rocket for propulsive purposes. ... John Drury Clark, Ph. ... Hypergolic rocket fuels spontaneously ignite when their two components come into contact with each other. ...

References

^ Hitoshi Habuka, Takahiro Sukenobu, Hideyuki Koda, Takashi Takeuchi, and Masahiko Aihara (2004). "Silicon Etch Rate Using Chlorine Trifluoride". Journal of the Electrochemical Society 151 (11): G783–G787. doi:10.1149/1.1806391.
^ United States Patent 5849092 "Process for chlorine trifluoride chamber cleaning"
^ Board on Environmental Studies and Toxicology, (BEST) (2006). Acute Exposure Guideline Levels for Selected Airborne Chemicals: Volume 5 (citation at the National Academies Press). Washington D.C.: National Academies Press, 40. ISBN 0-309-10358-4.
^ United States Patent 6034016 "Method for regenerating halogenated Lewis acid catalysts"
^ Otto Ruff, H. Krug (1931). "Über ein neues Chlorfluorid-CIF₃". Zeitschrift für anorganische und allgemeine Chemie 190 (1): 602–608. doi:10.1002/zaac.19301900127.
^ Air Products Safetygram. http://www.airproducts.com/nr/rdonlyres/8479ed55-2170-4651-a3d4-223b2957a9f3/0/safetygram39.pdf
^ "Bunker Tours" report on Falkenhagen
^ Clark, John D. (2001). Ignition!. UMI Books on Demand. ISBN 0-8135-0725-1.
^ ClF3/Hydrazine at the Encyclopedia Astronautica.

Groehler, Olaf (1989). Der lautlose Tod. Einsatz und Entwicklung deutscher Giftgase von 1914 bis 1945. Reinbek bei Hamburg: Rowohlt. ISBN 3-499-18738-8.
Ebbinghaus, Angelika (1999). Krieg und Wirtschaft: Studien zur deutschen Wirtschaftsgeschichte 1939–1945. Berlin: Metropol, 171–194. ISBN 3-932482-11-5.
Harold Simmons Booth, John Turner Pinkston, , Jr. (1947). "The Halogen Fluorides.". Chemical Reviews 41 (3): 421–439. doi:10.1021/cr60130a001.
Yu D Shishkov, A A Opalovskii (1960). "Physicochemical Properties of Chlorine Trifluoride". Russian Chemical Reviews 29 (6): 357–364. doi:10.1070/RC1960v029n06ABEH001237.
Robinson D. Burbank, Frank N. Bensey (1953). "The Structures of the Interhalogen Compounds. I. Chlorine Trifluoride at -120 °C". The Journal of Chemical Physics 21 (4): 602–608. doi:10.1063/1.1698975.
A. A. Banks and A. J. Rudge (1950). "The determination of the liquid density of chlorine trifluoride". Journal of the Chemical Society: 191–193. doi:10.1039/JR9500000191.
Lowdermilk, F. R.; Danehower, R. G.; Miller, H. C. (1951). "Pilot plant study of fluorine and its derivatives". Journal of Chemical Education 28: 246.

Note a: Using data from Economic History Services and The Inflation Calculator, we can calculate that 100 Reichsmark in 1941 is approximately equivalent to $540 US dollars in 2006. Reichsmark exchange rate values from 1942 to 1944 are fragmentary. A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Chemical Reviews (usually abbreviated as ), is a peer-reviewed scientific journal, published since 1900 by the American Chemical Society. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... The Journal of the Chemical Society was a scientific journal published from 1862 to 1877. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Journal of Chemical Education (JCE) is a monthly, subscription-only journal available in print and online. ...

Contents

Preparation, structure, and properties var ACE_AR = {Site: '756743', Size: '300250'};

Hazards

Military applications

Rocket propellant

References

External links

Preparation, structure, and properties