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
  • Gas phase ion energetics data
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • NIST Polycyclic Aromatic Hydrocarbon Structure Index
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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

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, References, Notes

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

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Ion clustering data, References, Notes

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

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to C₈H₁₀⁺ (ion structure unspecified)

Electron affinity determinations

Proton affinity at 298K

Gas basicity at 298K

Protonation entropy at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₈H₉^- +  =

By formula: C₈H₉^- + H⁺ = C₈H₁₀

Ion clustering 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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

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

Free energy of reaction

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

 +  = ( • )

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

( • ) +  = ( • 2)

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

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, 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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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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]

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Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Hammer, Diri, et al., 2003
Hammer, N.I.; Diri, K.; Jordan, K.D.; Desfrancois, C.; Compton, R.N., Dipole-bound anions of carbonyl, nitrile, and sulfoxide containing molecules, J. Chem. Phys., 2003, 119, 7, 3650-3660, https://doi.org/10.1063/1.1590959 . [all data]

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Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  T	Temperature
  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
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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