As benzene is ubiquitous in gasoline and hydrocarbon fuels that are in use everywhere, human exposure to benzene is a global health problem. Ethylbenzene Formula: C 8 H 10 Molecular weight: 106.1650 IUPAC Standard InChI: InChI=1S/C8H10/c1-2-8-6-4-3-5-7-8/h3-7H,2H2,1H3 IUPAC Standard InChIKey: YNQLUTRBYVCPMQ-UHFFFAOYSA-N CAS Registry Number: 100-41-4 Chemical structure: This structure is also available as a 2d Mol file or as a computed 3d SD file Recko, W.M., GSH is involved with the formation of phenylmercapturic acid. [all data], Williams and Daniels, 1925 Chlorination is achieved with chlorine to give chlorobenzene in the presence of a Lewis acid catalyst such as aluminium tri-chloride. Zhdanov, A.K., Each question paper and mark scheme will also comply with these . The maximum contaminant level goal (MCLG), a nonenforceable health goal that would allow an adequate margin of safety for the prevention of adverse effects, is zero benzene concentration in drinking water. 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. Sieg, L.; Crtzen, J.L. 14.3 g What is the oxidation number of carbon in C2O4? [all data], Ferguson and Miller, 1933 Applicability of the DuPont 900 DTA apparatus in quantitative differential thermal analysis, shall not be liable for any damage that may result from Eng. 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. 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. With the global phaseout of leaded gasoline, benzene has made a comeback as a gasoline additive in some nations. ; Karbalai Ghassemi, M.H., Benzene is used mainly as an intermediate to make other chemicals, above all ethylbenzene (and other alkylbenzenes), cumene, cyclohexane, and nitrobenzene. ; Smith, N.K., Willams, J.W. Benzene (CAS 71-43-2) 1 Carcinogenic to humans. Chem. Specific target organ toxicity - single exposure May cause drowsiness and dizziness. This intermediate distance is caused by electron delocalization: the electrons for C=C bonding are distributed equally between each of the six carbon atoms. Phys. The idea is used in fireworks to produce the colour. Derivatives of benzene occur sufficiently often as a component of organic molecules, so much so that the Unicode Consortium has allocated a symbol in the Miscellaneous Technical block with the code U+232C () to represent it with three double bonds,[62] and U+23E3 () for a delocalized version.[63]. [all data], Andrews, Lynn, et al., 1926 In the body, benzene is enzymatically converted to a series of oxidation products including muconic acid, phenylmercapturic acid, phenol, catechol, hydroquinone and 1,2,4-trihydroxybenzene. [all data], Burlew, 1940 BENZENE BNZ CAUTIONARY RESPONSE INFORMATION Common Synonyms Watery liquid Colorless Gasoline-like odor Floats on water. In general, the evaluated uncertainty limits are on the order of (0.5 to 2.5) kJ/mol. Calculate the number of joules required to melt 57.4 g of benzene at 5.5 degrees; The specific heat of toluene, C_7H_8, is 1.13 J/g K. The American Petroleum Institute (API) stated in 1948 that "it is generally considered that the only absolutely safe concentration for benzene is zero". Smaller amounts of benzene are used to make some types of rubbers, lubricants, dyes, detergents, drugs, explosives, and pesticides. We don't save this data. ; Wallace, J.H., Jr., Sandmeyer Reaction. This page provides supplementary chemical data on benzene. There are sufficient high-quality literature values to make a good evaluation with a high degree of confidence. J. Chem. Thermal and volumetric properties of chloroform + benzene mixtures and the ideal associated solution model of complex formation, The molecular conformation is stabilized by NHO and NHN intermolecular hydrogen-bonding interactions. Heat capacities of some organic liquids determined with the mixing calorimeter, Acta, 1967, 37, 200-208. Benzene Formula:C6H6 Molecular weight:78.1118 IUPAC Standard InChI:InChI=1S/C6H6/c1-2-4-6-5-3-1/h1-6HCopy IUPAC Standard InChIKey:UHOVQNZJYSORNB-UHFFFAOYSA-NCopy CAS Registry Number:71-43-2 Chemical structure: This structure is also available as a 2d Mol fileor as a computed3d SD file The 3d structure may be viewed using Javaor Javascript. [all data], Ahlberg, Blanchard, et al., 1937 1st Czech. ; Smith, J.F. In March 2006, the official Food Standards Agency in United Kingdom conducted a survey of 150 brands of soft drinks. 125129. In this hydrogen-intensive process, toluene is mixed with hydrogen, then passed over a chromium, molybdenum, or platinum oxide catalyst at 500650C and 2060 atm pressure. Izv. Ethyl alcohol likely exhibits more hydrogen bonding than water. In 1988 it was reported that two-thirds of all chemicals on the American Chemical Society's lists contained at least one benzene ring. 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. Benzene is more resistant to temperature change than sulfuric acid. Burlew, J.S., Several enzymes are involved. CYP2E1 is involved at multiple steps: converting benzene to oxepin (benzene oxide), phenol to hydroquinone, and hydroquinone to both benzenetriol and catechol. Copper standard solution,CAS Number:7440-50-8,Specification:50mL Inter. Are fluid 5. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. Toluene disproportionation (TDP) is the conversion of toluene to benzene and xylene. Data compiled as indicated in comments: Richards, W.T. 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. [9], 1919, 11, 253-291. 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 Thermodynam., 1982, 14, 259-268. The risk from exposure to 1 ppm for a working lifetime has been estimated as 5 excess leukemia deaths per 1,000 employees exposed. This amount is about 10 times the average daily intake of benzene by nonsmokers. In 1855, Hofmann used the word "aromatic" to designate this family relationship, after a characteristic property of many of its members. Excess properties of the mixture bis(2-dichlorethyl)ether (chlorex) + 2,2,4-trimethylpentane (isooctane), Soc., 1940, 62, 696-700. [101] After smoking 32 cigarettes per day, the smoker would take in about 1.8 milligrams (mg) of benzene. Specific target organ toxicity - repeated exposure Due to partial or complete lack of data the classification is not possible. Calorimetry (Lect. Faraday Soc., 1955, 51, 323-342. [all data], Rabinovich and Nikolaev, 1962 Hence the specific heat of benzene = 1716.475 J/kg.C. Eliminate heat and ignition sources such as sparks, open flames, hot surfaces and static The catechol is then metabolized to acetyl CoA and succinyl CoA, used by organisms mainly in the citric acid cycle for energy production. ; Gilmont, R.; Rossini, F.D., These intermediates and metabolites induce genotoxicity by multiple mechanisms including inhibition of topoisomerase II (which maintains chromosome structure), disruption of microtubules (which maintains cellular structure and organization), generation of oxygen free radicals (unstable species) that may lead to point mutations, increasing oxidative stress, inducing DNA strand breaks, and altering DNA methylation (which can affect gene expression). At the critical point there is no change of state when pressure is increased or if heat is added. specific heat liquid = 1.740 J/g C A 27.00 g sample of liquid benzene is initially at 41.30 C. Uber binare flussige Mischungen I. Mischungswarment, Volumseffekte und Zustandsdiagramme von chlorex mit benzol und n-alkylbenzolen, [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. Have high density 4. 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. Standard Reference Data Act. ; Tupman, W.I. : Molwarme des Systems 1,2-Dibromathan-Benzol, Toluene is also processed into benzene. Technology, Office of Data As a consequence, gasoline often contained several percent benzene before the 1950s, when tetraethyl lead replaced it as the most widely used antiknock additive. A typical reaction yield exceeds 95%. 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. 80.0C Boiling Point Melting Point Heat of Vaporization: Heat of Fusion 10.0C 10.0 kJ/mol 30.0 kJ/mol 100.0 J/mol K 90.0 J/mol K 70.0 J/mol K heat capacity . Ber. Soc., 1926, 48, 1274-1287. ; Inglese, A.; Wilhelm, E., Obshch. How much heat must be transferred to the mixture per g-mole of feed? Structure and properties . Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. The short term exposure limit for airborne benzene is 5 ppm for 15 minutes. [all data], Aoyama and Kanda, 1935 Monatsh. for disposal with other flammable, non-chlorinated solvents. Physik [3], 1881, 13, 447-464. The . Staveley, L.A.K. Data, 1969, 14, 102-106. In 1865, the German chemist Friedrich August Kekul published a paper in French (for he was then teaching in Francophone Belgium) suggesting that the structure contained a ring of six carbon atoms with alternating single and double bonds. J. Specific Heat capacity is given as. 1. Uchebn. American Conference of Governmental Industrial Hygienists (ACGIH) adopted Threshold Limit Values (TLVs) for benzene at 0.5 ppm TWA and 2.5 ppm STEL. Flow microcalorimeter for heat capacities of solutions, Specific target organ toxicity - single exposure (narcotic effects) - Category 3 - Narcotic effect. (1867) "Theoretische Betrachtungen und deren Anwendungen zur Systematik der organischen Chemie" (Theoretical considerations and their applications to the classification scheme of organic chemistry). A small-area case-crossover study", "Advances in understanding benzene health effects and susceptibility", American Petroleum Institute, API Toxicological Review, Benzene, September 1948, "Advances in Understanding Benzene Health Effects and Susceptibility", International Agency for Research on Cancer, IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs, "Benzene-induced cancers: abridged history and occupational health impact", "The toxicity of benzene and its metabolism and molecular pathology in human risk assessment", Occupational Safety and Health Standards, Toxic and Hazardous Substances, 1910.1028, Public Health Statement for Benzene, Agency for Toxic Substances and Disease Registry. ; Badalov, Yu.A., Myeloperoxidase mutations result in loss of function and may result in decreased generation of toxic metabolites. J. Chem. [all data], Fortier, Benson, et al., 1976 [86] These legal limits were based on studies demonstrating compelling evidence of health risk to workers exposed to benzene. J. Good, W.D. (August 2007). [25] In 1997, benzene was detected in deep space.[26]. J. The most important variations contain nitrogen. Surface area of the liquid c. Pressure 6. II., Reaxys Registry Number. Sci. Faraday Soc., 1971, 67, 2282-2291. Calorimetric determinations of thermal properties of methyl alcohol, ethyl alcohol, and benzene, J. Chem. cHliquid : Standard liquid enthalpy of combustion (kJ/mol). This was seven years after he had solved the problem of how carbon atoms could bond to up to four other atoms at the same time. Phys., 1937, 5, 537-551. Phys. Sci. [all data], Recko, 1968 Specific Heat of Benzene, Specific Heat of C6H6. Vys. The liquid product is 40.0 mole% B, and the vapor product is 68.4 mole% B. Contact China Manufactory Wuhan Kaimubuke Pharmaceutical Technology Co., Ltd for the product BERYLLIUM CHLORIDE. The temperatures of the distillate and rejected brine flowing from the preheaters are 45 C . J. Res. Benzene has 6 hydrogen atoms, fewer than the corresponding parent alkane, hexane, which has 14. [88][89] In September 1995, NIOSH issued a new policy for developing recommended exposure limits (RELs) for substances, including carcinogens. Heats of formation and chemical compositions . [all data], Shiohama, Ogawa, et al., 1988 [all data], Grolier, Wilhelm, et al., 1978 Wilhelm, E.; Faradjzadeh, A.; Grolier, J.-P.E., Equation 1. The use of mixing calorimeter for measuring heat capacities of liquids, : Dynamic viscosity (Pas). ; Shipova, V.A., Important examples include the sandwich and half-sandwich complexes, respectively, Cr(C6H6)2 and [RuCl2(C6H6)]2. ; Hart, K.R., lifetime movies list 2023; what does a call back interview mean; stashbox vape bmm; mens burberry belt; boa account number and tax id pdf 2022; Specific gravity: 0.87 Principal hazards *** Benzene is a carcinogen (cancer-causing agent). J. Class XII. Specific heat of benzenoid hydrocarbons, When plastic water pipes are subject to high heat, the water may be contaminated with benzene. In 1903, Ludwig Roselius popularized the use of benzene to decaffeinate coffee. Enthalpies of combustion of toluene, benzene, cyclohexane, cyclohexene, methylcyclopentane, 1-methylcyclopentene, and n-hexane, Ber. [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. Dokl. In liquid form,benzeneis clear, colorless and Thermodynam., 1976, 8, 411-423. [all data], Landrieu, Baylocq, et al., 1929 Specific heat of benzene= 1.80 . ; Extrapolation below 90 K, 47.49 J/mol*K.; p = 0.1 MPa. [102], Inhaled benzene is primarily expelled unchanged through exhalation. [all data], Willams and Daniels, 1924 J. Thermophysics, 1982, 3, 1-15. Similar problems were reported by the FDA in the United States.[104]. Univ. Williams, J.W. Rabinovich, I.B. Akad. A method for the determination of the specific heats of liquids, and a determination of the specific heats of aniline and benzene over the approximate range 20C to 50C, Excess molar isobaric heat capacities and isentropic compressibilities of (cis- or trans-decalin + benzene or toluene or iso-octane or n-heptane) at 298.15 K, at 1 atm: botling point = 80. and robots that compete in the performance of specific operational tasks. [all data], Deshpande and Bhatagadde, 1971 Chim., 1960, 8, 651-653. Thermodynam., 1982, 14, 523-529. France, 1929, 45, 36-49. We don't collect information from our users. Studies have shown that genotype at these loci may influence susceptibility to the toxic effects of benzene exposure. Please read AddThis Privacy for more information. Chem., 1971, 24, 1817-1822. on behalf of the United States of America. of Health and Human Services: TR-289: Toxicology and Carcinogenesis Studies of Benzene, NLM Hazardous Substances Databank Benzene, https://en.wikipedia.org/w/index.php?title=Benzene&oldid=1139445886, potential occupational carcinogen, flammable. [all data], Go To: Top, Condensed phase thermochemistry data, References. Am. ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein The affected batches were removed from sale. Ogawa, H.; Murakami, S., Vapors may travel to source of ignition and flash back. Thermodynam., 1988, 20, 1183-1189. Aust. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Examples of simple benzene derivatives are phenol, toluene, and aniline, abbreviated PhOH, PhMe, and PhNH2, respectively. 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. . Zaved. Using a precise scanning-microcalorimetric technique, the heat-capacity difference between water and an aqueous solution of benzene or of toluene has been measured for a broad temperature range (from 278 to 413 K) under excess pressure, and the partial specific heat capacity of these solutes has been determined. Soc. [all data], Czarnota, 1991 Ferguson, A.; Miller, J.T., Ann. The specific heat capacity of liquid water is 4.18 J/g-K. How many joules of heat are needed to raise the temperature of 5.00 g of water from 25.1C to 65.3C? Storage class Storage class (TRGS 510): 3: Flammable liquids 7.3 Specific end use(s) Apart from the uses mentioned in section 1.2 no other specific uses are stipulated SECTION 8: Exposure controls/personal protection Benzene. Specific heat of water= 4.18 . ; T = 93 to 300 K. Value is unsmoothed experimental datum. Khim., 1947, 17, 1999-2003. [64], Four chemical processes contribute to industrial benzene production: catalytic reforming, toluene hydrodealkylation, toluene disproportionation, and steam cracking etc. Chem., 1978, 82, 1282-1290. HHS Vulnerability Disclosure. ; Picker, P., J. Chem. The United States Environmental Protection Agency has set a maximum contaminant level for benzene in drinking water at 0.0005mg/L (5 ppb), as promulgated via the U.S. National Primary Drinking Water Regulations. ; El-Sharkawy, A.A.; Gasser, F.A., Proc. ), 1977, C9-1-C9-4. Shiohama, Y.; Ogawa, H.; Murakami, S.; Fujihara, I., [18][19] In 1833, Eilhard Mitscherlich produced it by distilling benzoic acid (from gum benzoin) and lime. [all data], Vesely, Svoboda, et al., 1977 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. [all data], Naziev, Bashirov, et al., 1986 Sci. Inzh-Fiz. (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". Thermodynam., 1991, 23, 25-30. Note: (s) notation indicates equilibrium temperature of vapor over solid, otherwise value is equilibrium temperature of vapor over liquid. Faraday Soc., 1956, 52, 753-763. [citation needed]. Atalla, S.R. [47][48] It was the German chemist Carl Grbe who, 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). [17] Kekul's 1890 speech[41] in which this anecdote appeared has been translated into English. Benzene was historically used as a significant component in many consumer products such as liquid wrench, several paint strippers, rubber cements, spot removers, and other products. The flow rates of the hot and cold stream in the preheaters are equal. The heat capacity of the system benzene + diphenylmethane, The heat capacity, heat of fusion and entropy of benzene, [all data], Rajagopal and Subrahmanyam, 1974 ; Nagano, Y., Thermodynam., 1974, 6, 873-876. Thus, a double bond would exist with one neighbor during the first interval and with the other neighbor during the next interval. Czech. Rastorguev, Yu.L. Wilhelm, E.; Grolier, J.-P.E. [100] About 50% of the entire nationwide (United States) exposure to benzene results from smoking tobacco or from exposure to tobacco smoke. von Reis, M.A., Chemical, physical and thermal properties of benzene:Values are given for liquid at 25oC /77oF / 298 K and 1 bara, if not other phase, temperature or pressure given. 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. The most widely practiced example of this reaction is the ethylation of benzene. Am. National Center for Biotechnology Information. For commercial use, until World War II, much of benzene was obtained as a by-product of coke production (or "coke-oven light oil") for the steel industry. Das Benzol." 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. The U.S. Occupational Safety and Health Administration (OSHA) has set a permissible exposure limit of 1 part of benzene per million parts of air (1 ppm) in the workplace during an 8-hour workday, 40-hour workweek. Ser. Cp values given for the pressure range 0.1 to 68.1 MPa. [all data], Findenegg, Gruber, et al., 1965 [all data], Richards and Wallace, 1932 The phase diagram of benzene is shown below the table. Vyssh. 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. Google use cookies for serving our ads and handling visitor statistics. An equimolar liquid mixture of benzene (B) and toluene (T) at 10C is fed continuously to a vessel in which the mixture is heated to 50C. Benzene is a chemical compound in gasoline. Heat capacities of some organic liquids determined with the Picker flow calorimeter, 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. [1]24, 1935, 107-115. [67], As a gasoline (petrol) additive, benzene increases the octane rating and reduces knocking. Q = joules = x 10^ joules. 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. NQ01 metabolizes benzoquinone toward polyphenols (counteracting the effect of MPO). Specific Heat The specific heat for some commonly used liquids and fluids is given in the table below. Etude thermochimique dans la serie furanique, For example, mutations in CYP2E1 increase activity and result in increased generation of toxic metabolites. Outdoor air may contain low levels of benzene from automobile service stations, wood smoke, tobacco smoke, the transfer of gasoline, exhaust from motor vehicles, and industrial emissions.
