p-Xylene

• Formula: C₈H₁₀
• Molecular weight: 106.1650
• IUPAC Standard InChI: InChI=1S/C8H10/c1-7-3-5-8(2)6-4-7/h3-6H,1-2H3 Copy

  
• IUPAC Standard InChIKey: URLKBWYHVLBVBO-UHFFFAOYSA-N Copy
• CAS Registry Number: 106-42-3
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • 1,4-Di(methyl-d3)benzene-d4
• Other names: Benzene, 1,4-dimethyl-; p-Dimethylbenzene; p-Xylol; 1,4-Dimethylbenzene; 1,4-Xylene; p-Methyltoluene; para-Xylene; Chromar; Scintillar; 4-Methyltoluene; NSC 72419; UN 1307; 1,4-dimethyl-benzene ( p-xylene)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • NIST Polycyclic Aromatic Hydrocarbon Structure Index
• Options:
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Gas phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
BS - Robert L. Brown and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-βT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kcal/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Reaction thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₈H₁₀ = (C₃H₉Si⁺ • C₈H₁₀)

Free energy of reaction

C₈H₉^- +  =

By formula: C₈H₉^- + H⁺ = C₈H₁₀

C₆H₇N⁺ +  = (C₆H₇N⁺ • )

By formula: C₆H₇N⁺ + C₈H₁₀ = (C₆H₇N⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

Free energy of reaction

C₈H₁₀⁺ +  = (C₈H₁₀⁺ • )

By formula: C₈H₁₀⁺ + C₈H₁₀ = (C₈H₁₀⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

C₉H₁₂⁺ +  = (C₉H₁₂⁺ • )

By formula: C₉H₁₂⁺ + C₈H₁₀ = (C₉H₁₂⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

 +  = ( • )

By formula: Cl^- + C₈H₁₀ = (Cl^- • C₈H₁₀)

Free energy of reaction

( • ) +  = ( • 2)

By formula: (Cr⁺ • C₈H₁₀) + C₈H₁₀ = (Cr⁺ • 2C₈H₁₀)

 +  = ( • )

By formula: Cr⁺ + C₈H₁₀ = (Cr⁺ • C₈H₁₀)

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), References, Notes

Data compiled by: Coblentz Society, Inc.

• LIQUID; PERKIN-ELMER; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• SOLUTION (10% IN CCl4 FOR 3800-1300, 10% IN CS2 FOR 1300-650, AND 10% CCl4 FOR 650-240 CM^-1) VERSUS SOLVENT; PERKIN-ELMER 521 (GRATING); DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• VAPOR (0.5 MICROLITER AT 195 C); NICOLET FTIR; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 CM^-1 cm^-1 resolution
• VAPOR (5 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); PERKIN-ELMER 180; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 1 CM^-1 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Data compiled by: Pamela M. Chu, Franklin R. Guenther, George C. Rhoderick, and Walter J. Lafferty

• gas; IFS66V (Bruker); 3-Term B-H Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Boxcar Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Happ Genzel Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); NB Strong Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Triangular Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution

Mass spectrum (electron ionization)

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heats of combustion and formation at 25°C of the alkylbenzenes through C₁₀H₁₄, and of the higher normal monoalkylbenzenes, J. Res. NBS, 1946, 36, 455-461. [all data]

Chao J., 1986
Chao J., Thermodynamic properties of key organic oxygen compounds in the carbon range C1 to C4. Part 2. Ideal gas properties, J. Phys. Chem. Ref. Data, 1986, 15, 1369-1436. [all data]

Pitzer K.S., 1943
Pitzer K.S., The thermodynamics and molecular structure of benzene and its methyl derivatives, J. Am. Chem. Soc., 1943, 65, 803-829. [all data]

Taylor W.J., 1946
Taylor W.J., Heats, equilibrium constants, and free energies of formation of the alkylbenzenes, J. Res. Nat. Bur. Stand., 1946, 37, 95-122. [all data]

Draeger J.A., 1981
Draeger J.A., Ideal gas thermodynamic properties of 1,4-dimethylbenzene, J. Chem. Phys., 1981, 74, 4748-4749. [all data]

Draeger, 1985
Draeger, J.A., The methylbenzenes II. Fundamental vibrational shifts, statistical thermodynamic functions, and properties of formation, J. Chem. Thermodyn., 1985, 17, 263-275. [all data]

Hossenlopp I.A., 1981
Hossenlopp I.A., Vapor heat capacities and enthalpies of vaporization of four aromatic and/or cycloalkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 423-428. [all data]

Coops, Mulder, et al., 1946
Coops, J.; Mulder, D.; Dienske, J.W.; Smittenberg, J., The heats of combustion of a number of hydrocarbons, Rec. Trav. Chim. Pays/Bas, 1946, 65, 128. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Richards and Barry, 1915
Richards, T.W.; Barry, F., The heats of combustion of aromatic hydrocarbons and hexamethylene, J. Am. Chem. Soc., 1915, 37, 993-1020. [all data]

Richards and Jesse, 1910
Richards, T.W.; Jesse, R.H., Jr., The heats of combustion of the octanes and xylenes, J. Am. Chem. Soc., 1910, 32, 268-298. [all data]

Messerly, Finke, et al., 1988
Messerly, J.F.; Finke, H.L.; Good, W.D.; Gammon, B.E., Condensed-phase heat capacities and derived thermodynamic properties for 1,4-dimethylbenzene, 1,2-diphenylethane, and 2,3-dimethylnaphthalene, J. Chem. Thermodynam., 1988, 20, 485-501. [all data]

Pitzer and Scott, 1943
Pitzer, K.S.; Scott, D.W., The thermodynamics and molecular structure of benzene and its methyl derivatives, J. Am. Chem. Soc., 1943, 65, 803-829. [all data]

Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Daniels, A.C., Thermal data on organic compounds. VII. The heat capacities, entropies and free energies of twelve aromatic hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1547-1558. [all data]

Tardajos, Aicart, et al., 1986
Tardajos, G.; Aicart, E.; Costas, M.; Patterson, D., Liquid structure and second-order mixing functions for benzene, toluene, and p-xylene with n-alkanes, J. Chem. Soc., Faraday Trans., 1986, 1 82, 2977-2987. [all data]

Fortier and Benson, 1979
Fortier, J.-L.; Benson, G.C., Heat capacities of some binary aromatic hydrocarbon mixtures containing benzene or toluene, J. Chem. Eng. Data, 1979, 24(1), 34-37. [all data]

Ott, Goates, et al., 1979
Ott, J.B.; Goates, J.R.; Grigg, R.B., Excess volumes, enthalpies, and Gibbs free energies for mixtures of benzenes + p-xylene, J. Chem. Thermodynam., 1979, 11, 1167-1173. [all data]

Fortier and Benson, 1977
Fortier, J.-L.; Benson, G.C., Excess heat capacities of binary mixtures of tetrachloromethane witlh some aromatic liquids at 298.15 K, J. Chem. Thermodynam., 1977, 9, 1181-1188. [all data]

Wilhelm, Grolier, et al., 1977
Wilhelm, E.; Grolier, J.-P.E.; Karbalai Ghassemi, M.H., Molar heat capacities of binary liquid mixtures: 1,2-dichloroethane + benzene, + toluene, and + p-xylene, Ber. Bunsenges. Phys. Chem., 1977, 81, 925-930. [all data]

Hyder Khan and Subrahmanyam, 1971
Hyder Khan, V.; Subrahmanyam, S.V., Excess thermodynamic functions of the systems: benzene + p-xylene and benzene + p-dioxan, Trans. Faraday Soc., 1971, 67, 2282-2291. [all data]

Swietoslawski and Zielenkiewicz, 1958
Swietoslawski, W.; Zielenkiewicz, A., Mean specific heats of binary positive azeotropes, Bull. Acad. Pol. Sci. Ser. Sci. Chim., 1958, 6, 367-369. [all data]

Corruccini and Ginnings, 1947
Corruccini, R.J.; Ginnings, D.C., The enthalpy, entropy and specific heat of liquid p-xylene from 0 to 300°. The heat of fusion, J. Am. Chem. Soc., 1947, 69, 2291-2294. [all data]

Kurbatov, 1947
Kurbatov, V.Ya., Specific heat of liquids. I. Specific heat of benzenoid hydrocarbons, Zhur. Obshch. Khim., 1947, 17, 1999-2003. [all data]

Willams and Daniels, 1924
Willams, J.W.; Daniels, F., The specific heats of certain organic liquids at elevated temperatures, J. Am. Chem. Soc., 1924, 46, 903-917. [all data]

Messerly, Finke, et al., 1988, 2
Messerly, J.F.; Finke, H.L.; Good, W.D.; Gammon, B.E., Condensed-phase heat capacities and derived thermodynamic properties for 1,4-dimethylbenzene, 1,2-diphenylethane, and 2,3-dimethylnaphthalene, J. Chem. Thermodyn., 1988, 20, 485. [all data]

Huffman, Parks, et al., 1930, 2
Huffman, H.M.; Parks, G.S.; Daniels, A.C., Thermal Data on Organic Compounds: VII The Heat Capacities, Entropies and Free Energies of Twelve Aromatic Hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1547-58. [all data]

Tsonopoulos and Ambrose, 1995
Tsonopoulos, C.; Ambrose, D., Vapor-Liquid Critical Properties of Elements and Compounds. 3. Aromatic Hydrocarbons, J. Chem. Eng. Data, 1995, 40, 547-558. [all data]

Akhundov and Imanov, 1970
Akhundov, T.S.; Imanov, Sh.Yu., Teplofiz. Svoistva Zhidk., 1970, 1970, 48-55. [all data]

Simon, 1957
Simon, M., Methods and Apparatus Used at the Bureau of Physicochemical Standards XV. Critical Constants and Straight-Line Diameters of Ten Hydrocarbons, Bull. Soc. Chim. Belg., 1957, 66, 375-81. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Hossenlopp and Archer, 1988
Hossenlopp, I.A.; Archer, D.G., Enthalpies of vaporization of piperidine and 1,2-dimethylbenzene; gas-phase isobaric heat capacities of piperidine, The Journal of Chemical Thermodynamics, 1988, 20, 9, 1061-1068, https://doi.org/10.1016/0021-9614(88)90112-7 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Osborn and Douslin, 1974
Osborn, Ann G.; Douslin, Donald R., Vapor-pressure relations for 15 hydrocarbons, J. Chem. Eng. Data, 1974, 19, 2, 114-117, https://doi.org/10.1021/je60061a022 . [all data]

Natarajan and Viswanath, 1985
Natarajan, Govindarajan; Viswanath, Dabir S., Enthalpy of vaporization and vapor pressure of benzene, toluene, p-xylene, and tetralin between 1 and 16 bar, J. Chem. Eng. Data, 1985, 30, 2, 137-140, https://doi.org/10.1021/je00040a001 . [all data]

Castellari, Francesconi, et al., 1982
Castellari, Carlo; Francesconi, Romolo; Comelli, Fabio, Vapor-liquid equilibriums in binary systems containing 1,3-dioxolane at isobaric conditions. 3. Binary mixtures of 1,3-dioxolane with o-, m-, and p-xylenes, J. Chem. Eng. Data, 1982, 27, 2, 156-158, https://doi.org/10.1021/je00028a017 . [all data]

Gaw and Swinton, 1968
Gaw, W.J.; Swinton, F.L., Thermodynamic properties of binary systems containing hexafluorobenzene. Part 4.?Excess Gibbs free energies of the three systems hexafluorobenzene + benzene, touene, and p-xylene, Trans. Faraday Soc., 1968, 64, 2023, https://doi.org/10.1039/tf9686402023 . [all data]

Willingham, Taylor, et al., 1945
Willingham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor pressures and boiling points of some paraffin, alkylcyclopentane, alkylcyclohexane, and alkylbenzene hydrocarbons, J. RES. NATL. BUR. STAN., 1945, 35, 3, 219-17, https://doi.org/10.6028/jres.035.009 . [all data]

Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D., Vapor pressures and boiling points of sixty API-NBS hydrocarbons, J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050 . [all data]

Ambrose, Broderick, et al., 1967
Ambrose, D.; Broderick, B.E.; Townsend, R., The Vapour Pressures Above the Normal Boiling Point and the Critical Pressures of Some Aromatic Hydrocarbons, J. Chem. Soc. A:, 1967, 633-641, https://doi.org/10.1039/j19670000633 . [all data]

Williamham, Taylor, et al., 1945
Williamham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor Pressures and Boiling Points of Some Paraffin, Alkylcyclopentane, Alkylcyclohexane, and Alkylbenzene Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1945, 35, 3, 219-244, https://doi.org/10.6028/jres.035.009 . [all data]

Hessler and Lichtenstein, 1986
Hessler, W.; Lichtenstein, W., Wiss. Zeitschr. Wilhelm-Pieck-Univ. Rostock, Naturwiss. Reihe, 1986, 35, 7, 27. [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Wojtyniak and Stone, 1986
Wojtyniak, A.C.M.; Stone, A.J., A High-Pressure Mass Spectrometric Study of the Bonding of Trimethylsilylium to Oxygen and Aromatic Bases, Can. J. Chem., 1986, 74, 59. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Meot-Ner (Mautner) and El-Shall, 1986
Meot-Ner (Mautner), M.; El-Shall, M.S., Ionic Charge Transfer Complexes. 1. Cationic Complexes with Delocalized and Partially Localized pi Systems, J. Am. Chem. Soc., 1986, 108, 15, 4386, https://doi.org/10.1021/ja00275a026 . [all data]

Meot-Ner (Mautner), Hamlet, et al., 1978
Meot-Ner (Mautner), M.; Hamlet, P.; Hunter, E.P.; Field, F.H., Bonding Energies in Association Ions of Aromatic Molecules. Correlations with Ionization Energies, J. Am. Chem. Soc., 1978, 100, 17, 5466, https://doi.org/10.1021/ja00485a034 . [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [all data]

Lin and Dunbar, 1997
Lin, C.-Y.; Dunbar, R.C., Radiative Association Kinetics and Binding Energies of Chromium Ions with Benzene and Benzene Derivatives, Organometallics, 1997, 16, 12, 2691, https://doi.org/10.1021/om960949n . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  T	Temperature
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Vc	Critical volume
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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