specific heat of benzene

Benzene is used mainly as an intermediate to make other chemicals, above all ethylbenzene (and other alkylbenzenes), cumene, cyclohexane, and nitrobenzene. In 1870, the German chemist . 2. Is benzene solid or liquid? Czarnota, I., ; Simonov, V.M. for disposal with other flammable, non-chlorinated solvents. 14.3 g What is the oxidation number of carbon in C2O4? Experimental device for measurement of isobaric specific heat of electrolytes at elevated pressures, Cookies are only used in the browser to improve user experience. to the boiling point, How much heat must be transferred to the mixture per g-mole of feed? [all data], Rabinovich and Nikolaev, 1962 J. Chem. Thermodynam., 1982, 14, 259-268. [88][89] In September 1995, NIOSH issued a new policy for developing recommended exposure limits (RELs) for substances, including carcinogens. Benzene is less dense thanwaterand is slightly soluble inwater. Equation 1. Kurbatov, V.Ya., Ferguson, A.; Miller, J.T., Unsmoothed experimental datum given as 1.7915 kJ/kg*K.; T = 283.78 to 348.47 K. Cp = 1.3943 - 5.857x10-4T + 5.89x10-6T2 kJ/kg*K. Cp value calculated from equation. Soc. Excess volumes and excess heat capacities of tetrachloroethene + cyclohexane, + methylcyclohexane, + benzene, and + toluene at 298.15 K, When gasoline burns, the benzene reacts with oxygen. Occupational Exposures Chemical Carcinogens & Mutagens - scribd.com J. Thermophysics, 1982, 3, 1-15. France, 1929, 45, 36-49. Several enzymes are involved. Centric affinities (i.e., bonds) acted within a designated cycle of carbon atoms. Partial Vaporization of a Mixture An equimolar liquid mixture of Diffuse through otherliquids 6. ; Ganiev, Yu.A., Applicability of the DuPont 900 DTA apparatus in quantitative differential thermal analysis, According to the ATSDR Toxicological Profile for benzene, between 1978 and 1981, catalytic reformates accounted for approximately 4450% of the total U.S benzene production.[52]. The specific heat of liquid water is 4.184 J/g C and the specific heat of steam is 1.99 J/g C. H vapof water = 40.8 kJ/mol. As benzene can cause cancer, NIOSH recommends that all workers wear special breathing equipment when they are likely to be exposed to benzene at levels exceeding the REL (10-hour) of 0.1 ppm. Heats of combustion of benzene, toluene, ethyl-benzene, o-xylene, m-xylene, p-xylene, n-propylbenzene, and styrene, Conf. ; Wilhelm, E.; Hamedi, M.H., Ethylbenzene | C6H5C2H5 or C8H10 | CID 7500 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities . Devon is applying 100N of . Substance Specific heat capacity (J/g C) lead 0.128 silver 0.235 copper 0.385 iron 0.449 aluminum 0.903 water 4.184 An unknown substance has a mass of 14.5 g.14.5 g. The temperature of the substance increases by 15.3 C15.3 C when 85.4 J85.4 J of heat is added to the substance. 2021 by the U.S. Secretary of Commerce ; Extrapolation below 90 K, 47.49 J/mol*K.; p = 0.1 MPa. Phys. Step-by-Step Verified Solution Basis: 1 mol Feed Toluene hydrodealkylation converts toluene to benzene. Am. Most of these metabolites have some value as biomarkers of human exposure, since they accumulate in the urine in proportion to the extent and duration of exposure, and they may still be present for some days after exposure has ceased. on behalf of the United States of America. For example, mutations in CYP2E1 increase activity and result in increased generation of toxic metabolites. Chem., 1971, 24, 1817-1822. [all data], Kalali, Kohler, et al., 1987 Therefore, between the carbon atoms of benzene there were no fixed (i.e., constant) and distinct single or double bonds; instead, the bonds between the carbon atoms were identical. Data compiled as indicated in comments: The short term exposure limit for airborne benzene is 5 ppm for 15 minutes. Short Commun. Approximately 24,700,000 tons were produced in 1999. Glutathione seems to play an important role by protecting against benzene-induced DNA breaks and it is being identified as a new biomarker for exposure and effect. For a given species, see the thermodynamic values below. [1]24, 1935, 107-115. heat [1] 3. Bunsenges. Thermodynam., 1976, 8, 411-423. Int. The aromatic products of the reaction are then separated from the reaction mixture (or reformate) by extraction with any one of a number of solvents, including diethylene glycol or sulfolane, and benzene is then separated from the other aromatics by distillation. Please read AddThis Privacy for more information. : Dynamic viscosity (Pas). Get the detailed answer: What is the specific heat of benzene? \Delta H of fusion for benzene is 9.87 kJ/mol; specific heat for liquid benzene is 1.63 J/g X degrees). [39] This vision, he said, came to him after years of studying the nature of carbon-carbon bonds. National Library of Medicine. Eng. Am. Faraday Soc., 1956, 52, 753-763. Zhur., 1986, 51(5), 789-795. The measurement of benzene in humans can be accomplished via urine, blood, and breath tests; however, all of these have their limitations because benzene is rapidly metabolized in the human body. Via hydrogenation, benzene and its derivatives convert to cyclohexane and derivatives. (2007), Last edited on 15 February 2023, at 05:01, United States Environmental Protection Agency, US Department of Health and Human Services, Agency for Toxic Substances and Disease Registry, Occupational Safety and Health Administration, National Institute for Occupational Safety and Health, an explosion at a China National Petroleum Corporation (CNPC) factory, Industrial Union Department v. American Petroleum Institute, Industrial & Engineering Chemistry Chemical & Engineering Data Series, "Surface tension measurements show that chaotropic salting-in denaturants are not just water-structure breakers", Proceedings of the National Academy of Sciences of the United States of America, "Benzene - an overview | ScienceDirect Topics", "On new compounds of carbon and hydrogen, and on certain other products obtained during the decomposition of oil by heat", Philosophical Transactions of the Royal Society, "ber das Benzol und die Suren der Oel- und Talgarten", Reports of the Proceedings of the Scientific Society of Freiburg, "On the oxidation of phenyl alcohol, and a mechanical arrangement adapted to illustrate structure in the non-saturated hydrocarbons", Proceedings of the Royal Society of Edinburgh, "Sur la constitution des substances aromatiques", "Ueber einige Condensationsproducte des Aldehyds", "An explanation of the laws which govern substitution in the case of benzenoid compounds", "Crocker, Not Armit and Robinson, Begat the Six Aromatic Electrons". [79][80], According to the Agency for Toxic Substances and Disease Registry (ATSDR) (2007), benzene is both a synthetically-made and naturally occurring chemical from processes that include: volcanic eruptions, wild fires, synthesis of chemicals such as phenol, production of synthetic fibers, and fabrication of rubbers, lubricants, pesticides, medications, and dyes. 2039504. See also the following documents for changes in benzene properties with changes in pressure and temperature: See also more about atmospheric pressure, and STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure, as well as Thermophysical properties of: Acetone, Acetylene, Air, Ammonia, Argon, Butane, Carbon dioxide, Carbon monoxide, Ethane, Ethanol, Ethylene, Helium, Hydrogen, Hydrogen sulfide, Methane, Methanol, Nitrogen, Oxygen, Pentane, Propane, Toluene, Water and Heavy water, D2O. The molecule is planar. PubChem Substance ID. Uber binare flussige Mischungen I. Mischungswarment, Volumseffekte und Zustandsdiagramme von chlorex mit benzol und n-alkylbenzolen, [all data], Andrews, Lynn, et al., 1926 Thermodynam., 1982, 14, 523-529. [all data], Rajagopal and Subrahmanyam, 1974 Thermodynam., 1988, 20, 1183-1189. Chem. Pyrolysis gasoline can be blended with other hydrocarbons as a gasoline additive, or routed through an extraction process to recover BTX aromatics (benzene, toluene and xylenes). 8600 Rockville Pike, Bethesda, MD, 20894 USA. Lesson13 Flashcards | Quizlet J. Data, 1986, 31, 238-240. Solution Chem., 1987, 16, 745-752. Sometimes, higher temperatures are used instead of a catalyst (at the similar reaction condition). Monatsh. Chem., 1977, 81, 925-930. Investigation of stoichiometric methane/air/benzene (1.5%) and methane The pure material, and any solutions containing it, constitute a fire risk. In heterocycles, carbon atoms in the benzene ring are replaced with other elements. Die specifische Wrme flssiger organischer Verbindungen und ihre Beziehung zu deren Moleculargewicht, Google use cookies for serving our ads and handling visitor statistics. It is also used in water treatment chemicals, paper sizing, artificial sweeteners, flavor enhancers, cosmetics, and lubricants. To provide a mechanism for the conversion process, Kekul proposed that the valency of an atom is determined by the frequency with which it collided with its neighbors in a molecule. Monatsh. Enthalpies of combustion of toluene, benzene, cyclohexane, cyclohexene, methylcyclopentane, 1-methylcyclopentene, and n-hexane, [38] Kekul's symmetrical ring could explain these curious facts, as well as benzene's 1:1 carbon-hydrogen ratio. The current NIOSH definition for an IDLH condition, as given in the NIOSH Respirator Selection Logic, is one that poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment. Kalali, H.; Kohler, F.; Svejda, P., In industrybenzeneis used as a solvent, as a chemical intermediate, and is used in the synthesis of numerous chemicals. It also shows the saturation pressure with changes in temperature. Soc. Soc., 1925, 47, 1-9. de Kolossowsky, N.A. American Conference of Governmental Industrial Hygienists (ACGIH) adopted Threshold Limit Values (TLVs) for benzene at 0.5 ppm TWA and 2.5 ppm STEL. [100] About 50% of the entire nationwide (United States) exposure to benzene results from smoking tobacco or from exposure to tobacco smoke. ; Daniels, F., This is often called "on-purpose" methodology to produce benzene, compared to conventional BTX (benzene-toluene-xylene) extraction processes. A mixture of 54.5 mol% benzene in chlorobenzene at its bubble point is fed continuously to the bottom plate of a column containing two equilibrium plates, with a partial reboiler and a total condenser. Coll. Heats of combustion and formation at 25C of the alkylbenzenes through C10H14, and of the higher normal monoalkylbenzenes, Specific heats of some liquids and azeotropic mixtures, Naziev, Ya.M. J. ; Smith, J.F. Instead, retain in a safe place in the laboratory (well away from any source of ignition). Archibald Scott Couper in 1858 and Johann Josef Loschmidt in 1861[36] suggested possible structures that contained multiple double bonds or multiple rings, but too little evidence was then available to help chemists decide on any particular structure. When certain compounds are heated, light is emitted because the compounds CONVERT some of the energy from the heating into coloured light of specific colours. As the carbon atoms in the benzene ring collided with each other, each carbon atom would collide twice with one neighbor during a given interval and then twice with its other neighbor during the next interval. [all data], Recko, 1968 shall not be liable for any damage that may result from Molar heat capacities of binary liquid mixtures: 1,2-dichloroethane + benzene, + toluene, and + p-xylene, Excess properties of the mixture bis(2-dichlorethyl)ether (chlorex) + 2,2,4-trimethylpentane (isooctane), Pressions maxima des vapeurs du benzene et du cyclohexane aux temperatures moyennes et calcul de leurs chaleurs specifiques principales, biphenyl (aka diphenyl) at higher temperature: If the raw material stream contains much non-aromatic components (paraffins or naphthenes), those are likely decomposed to lower hydrocarbons such as methane, which increases the consumption of hydrogen. Excess heat capacities for mixture of benzene with n-heptane at 293.15, 298.15 and 303.15 K, J. Chem. Tohoku Imp. Temperature and Pressure - Online calculator, figures and table showing density and specific weight of benzene, C 6 H 6, at temperatures ranging from 5 to 325 C (42 to 620 F) at atmospheric and higher pressure - Imperial and SI Units. Heat capacity of benzene at high pressures, In some systems, even the benzene-to-xylenes ratio is modified to favor xylenes. Combustible Gas Leak LEL Natural Gas Detector Methane Benzene Propane Alarm. Grolier, J.-P.E. Die aromatischen Verbindungen. [all data], Gorbunova, Simonov, et al., 1983 The aromatic compounds. If benzene must be used in an experiment, it should be handled at all stages in a fume cupboard. The curve between the critical point and the triple point shows the benzene boiling point with changes in pressure. [67], As a gasoline (petrol) additive, benzene increases the octane rating and reduces knocking. ASU CHM 118 FINAL EXAM Flashcards | Quizlet Chim. Have definite shape (resist deformation) 2. Am. Replacement of a second CH bond with N gives, depending on the location of the second N, pyridazine, pyrimidine, or pyrazine. ; Karbalai Ghassemi, M.H., Sci. When plastic water pipes are subject to high heat, the water may be contaminated with benzene. Heat capacities of some organic liquids determined with the mixing calorimeter, The U.S. National Institute for Occupational Safety and Health (NIOSH) revised the Immediately Dangerous to Life and Health (IDLH) concentration for benzene to 500 ppm. Mean specific heat in homologous series of binary and ternary positive azeotropes, Benzene causes central nervous system damage acutely and bone marrow damage chronically and is carcinogenic. Trans. In 1872, Kekul suggested that benzene had two complementary structures and that these forms rapidly interconverted, so that if there were a double bond between any pair of carbon atoms at one instant, that double bond would become a single bond at the next instant (and vice versa). The temperatures of the distillate and rejected brine flowing from the preheaters are 45 C . In a human study 16.4 to 41.6% of retained benzene was eliminated through the lungs within five to seven hours after a two- to three-hour exposure to 47 to 110 ppm and only 0.07 to 0.2% of the remaining benzene was excreted unchanged in the urine. Data, 1969, 14, 102-106. GSH is involved with the formation of phenylmercapturic acid. ; Bashirov, M.M. See also tabulated values of specific heat of gases, food and foodstuff, metals and semimetals, common solids and other common substances as well as values of molar heat capacity of common organic substances and inorganic substances. Thermodynam., 1982, 14, 1199-1200. Sci. Sci. 1. NBS, 1946, 36, 455-461. Benzene - Thermophysical properties - Engineering ToolBox [all data], Czarnota, 1991 Das Benzol." Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! The major sources of benzene exposure are tobacco smoke, automobile service stations, exhaust from motor vehicles, and industrial emissions; however, ingestion and dermal absorption of benzene can also occur through contact with contaminated water. In the absence of the catalyst, benzene is impervious to hydrogen. Excess thermodynamic functions of the systems: benzene + p-xylene and benzene + p-dioxan, The heat capacity, heat of fusion and entropy of benzene, Aoyama, S.; Kanda, E., Wilhelm, E.; Grolier, J.-P.E. [103], Under specific conditions and in the presence of other chemicals benzoic acid (a preservative) and ascorbic acid (Vitamin C) may interact to produce benzene. Neft Gaz. These aberrations can be monitored using fluorescent in situ hybridization (FISH) with DNA probes to assess the effects of benzene along with the hematological tests as markers of hematotoxicity. We don't collect information from our users. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. ; T = 9 to 80C, mean Cp, five temperatures. [96], The paradigm of toxicological assessment of benzene is shifting towards the domain of molecular toxicology as it allows understanding of fundamental biological mechanisms in a better way. J. Chem. Shiohama, Y.; Ogawa, H.; Murakami, S.; Fujihara, I., Ahlberg, J.E. Aspiration hazard - Category 1 The signal word is danger. ; Wilhelm, E.; Grolier, J.-P.E., Are fluid 5. Heat capacities of some organic substances at low temperature, Complete decarboxylation of mellitic acid gives benzene. J. Phys. Benzene - NIST Temperature and Pressure - Online calculator, figures and table showing density and specific weight of benzene, C 6 H 6, at temperatures ranging from 5 to 325 C (42 to 620 F) at atmospheric and higher pressure - Imperial and SI Units. National Institutes of Health. ; Everett, D.H., Chem. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Hyder Khan, V.; Subrahmanyam, S.V., Molecular Formula / Molecular Weight. HHS Vulnerability Disclosure. [76] There is no safe exposure level; even tiny amounts can cause harm. [18][19] In 1833, Eilhard Mitscherlich produced it by distilling benzoic acid (from gum benzoin) and lime. [all data], Zhdanov, 1941 [all data], Fortier and Benson, 1976 National Center for Biotechnology Information. Copyright for NIST Standard Reference Data is governed by Have high density 4. Specific Heat of Benzene, Specific Heat of C6H6. Benzoic acid and its salts undergo decarboxylation to benzene. Excess heat capacities of binary liquid mixtures determined with a Picker flow calorimeter, Reproductive toxicity Suspected of damaging fertility or the unborn child. Am. Kekul's 1872 modification of his 1865 theory, illustrating rapid alternation of double bonds[note 1], In 1845, Charles Blachford Mansfield, working under August Wilhelm von Hofmann, isolated benzene from coal tar. Containers may explode when heated. Charles Mansfield filed for (November 11, 1847) and received (May 1848) a patent (no. (1-Ethylpropyl)benzene 1196-58-3 | Tokyo Chemical Industry Co., Ltd.(APAC) [all data], Willams and Daniels, 1924 Title: Microsoft Word - 9701_s19_ms_41 Author: whitej Created Date: 8/6/2019 11:46:17 AM . Specific Heat The specific heat for some commonly used liquids and fluids is given in the table below. The reaction involves the acylation of benzene (or many other aromatic rings) with an acyl chloride using a strong Lewis acid catalyst such as aluminium chloride or Iron(III) chloride. Cp,gas : Ideal gas heat capacity (J/molK). Nitric Oxide Is a Regulator of Hematopoietic Stem Cell Activity He gave the compound the name benzin. National Institute of Standards and [all data], Go To: Top, Condensed phase thermochemistry data, References. ; Hepler, L.G., Database and to verify that the data contained therein have Chim. It is produced by the oxidation of benzene or n-butane in the presence of vanadium oxide catalysts. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Many important chemical compounds are derived from benzene by replacing one or more of its hydrogen atoms with another functional group. Ser. Eng. [86] These legal limits were based on studies demonstrating compelling evidence of health risk to workers exposed to benzene. How To Remove Vinyl Print From A T-Shirt - Homelization Eliminate heat and ignition sources such as sparks, open flames, hot surfaces and static It takes 11.2 kJ of energy to raise the temperature of 145 g of benzene The reaction of the diazonium compound derived from aniline with hypophosphorus acid gives benzene. Specific heat of water= 4.18 . Solved 2. A mixture of \( 54.5 \mathrm{~mol} \% \) benzene | Chegg.com Commun., 1979, 44, 3529-3532. Benzene (data page) - Wikipedia [all data], Landrieu, Baylocq, et al., 1929 Heats of formation and chemical compositions . Google use cookies for serving our ads and handling visitor statistics. The most important variations contain nitrogen. In another human study, 30% of absorbed dermally applied benzene, which is primarily metabolized in the liver, was excreted as phenol in the urine. [82], OSHA regulates levels of benzene in the workplace. [all data], Fortier, Benson, et al., 1976 J. Chem. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. Pure benzene, for example, oxidizes in the body to produce an epoxide, benzene oxide, which is not excreted readily and can interact with DNA to produce harmful mutations. ; Blanchard, E.R. ; Kohler, F., Am. Ber. The most common reactions of benzene involve substitution of a proton by other groups. Heat capacity of benzene and of toluene from 8C. [all data], Maass and Walbauer, 1925 ; Wallace, J.H., Jr., Answered: Benzene is a chemical compound in | bartleby Structure and properties. J. Chem. phys. Zhur. [75][95], Genetic polymorphisms in these enzymes may induce loss of function or gain of function. Benzene - Wikipedia Chem., 1978, 82, 1282-1290. Standard Reference Data Act. Vapors may form explosive mixtures with air. Tanaka, R., In this process, the xylene stream exiting the TDP unit is approximately 90% p-xylene. Keep locked up or in an area accessible only to qualified or authorized persons. Good, W.D. Measurement of the heat capacity of a small volume of liquid by the piezo-thermometric method. [97] Benzene causes chromosomal aberrations in the peripheral blood leukocytes and bone marrow explaining the higher incidence of leukemia and multiple myeloma caused by chronic exposure. Replacing one CH with N gives the compound pyridine, C5H5N. In addition to the standard 4 confined space gases which include combustibles, O2, CO, & H2S, the GX-6000 has 2 additional smart channels that accept . Sieg, L.; Crtzen, J.L. 2 C6H6 + 15 0212 CO2 + 6HO + 1562 kcal How much heat is given off when 877 g (one liter) of benzene reacts with oxygen? [22] Four years later, Mansfield began the first industrial-scale production of benzene, based on the coal-tar method. in 1869, first used the prefixes ortho-, meta-, para- to denote specific relative locations of the substituents on a di-substituted aromatic ring (viz, naphthalene). Vapors may travel to source of ignition and flash back. 9.11 Ratio of Specific Heats of Vapor (Gas): 1.061 9.12 Latent Heat of Vaporization: 169 Btu/lb = 94.1 cal/g = 3.94 X 105 J/kg Benzene is more resistant to temperature change than sulfuric acid. Specific heat of liquids. Answered: The table lists the specific heat | bartleby Sci. number of sigma and pi bonds in benzene ; Daniels, A.C., Rept. It is dangerous to try to dispose of benzene by washing it down a sink, since it is toxic, will cause environmental damage, and presents a fire risk. 10, 1967, No.1, 79-82. ), pp. Soc., 1924, 46, 903-917. The empirical formula for benzene was long known, but its highly polyunsaturated structure, with just one hydrogen atom for each carbon atom, was challenging to determine. 1196-58-3. Curr. The specific heat capacity of benzene (C6H6) is 1.74 J/gK. What is its Benzene is sufficiently nucleophilic that it undergoes substitution by acylium ions and alkyl carbocations to give substituted derivatives. Benzene and cyclohexane have a similar structure, only the ring of delocalized electrons and the loss of one hydrogen per carbon distinguishes it from cyclohexane. [all data], Tanaka, 1985 Gorbunova, N.I. Sufficient heat is supplied to the reboiler to give, V /F = 0.855, and the reflux ratio L/D in the top of the column is constant at 0.50. If the sample is heated at constant pressure (P = 1 atm), calculate the amount of energy in kJ needed to raise the temperature of the sample to 102.70 C. Data, 1989, 34, 332-335. ; Nagano, Y., cHliquid : Standard liquid enthalpy of combustion (kJ/mol). "Zur Kenntnis der ungesttigen Verbindungen,", "Untersuchungen ber aromatische Verbindungen (Investigations of aromatic compounds)", "The Structure of the Benzene Ring in Hexamethylbenzene", "An X-Ray Analysis of the Structure of Hexachlorobenzene, Using the Fourier Method", "Meet Kathleen Lonsdale, the physicist and prison reformer who cracked benzene's code", "Faits pour servir la dtermination du lieu chimique dans la srie aromatique", "Untersuchungen ber die Constitution der zweifach-substituirten Benzole", "Life on Mars? Tanaka, R., Zur Thermodynamik von Mischphasen IX. MSDS for benzene is available at AMOCO. Benzene is an excellent ligand in the organometallic chemistry of low-valent metals. [65] More than half of the entire benzene production is processed into ethylbenzene, a precursor to styrene, which is used to make polymers and plastics like polystyrene. Explain how the vaporization of a liquid is affected by increasing the: a. Reaxys Registry Number. [all data], Grolier, Roux-Desgranges, et al., 1993 Table data obtained from CRC Handbook of Chemistry and Physics 44th ed. Benzene causes cancer in animals including humans. Kalorimetrische Messungen an Mischungen von Nichtelektrolyten, 1. Temperature. It is highly recommended to seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its directions. Uchebn. Tanaka, R., The phase diagram of benzene is shown below the table. In general, the evaluated uncertainty limits are on the order of (0.5 to 2.5) kJ/mol. The title compound, C18H16N2O2, is a precusor for the synthesis of polyimides. [30][37] Kekul used evidence that had accumulated in the intervening yearsnamely, that there always appeared to be only one isomer of any monoderivative of benzene, and that there always appeared to be exactly three isomers of every disubstituted derivativenow understood to correspond to the ortho, meta, and para patterns of arene substitutionto argue in support of his proposed structure.

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