p-Xylene

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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

Quantity Value Units Method Reference Comment
Δfgas17.9 ± 1.0kJ/molCcbProsen, Johnson, et al., 1946ALS

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
44.6750.Chao J., 1986Among the known statistically calculated values [ Pitzer K.S., 1943, Taylor W.J., 1946, Draeger J.A., 1981, Draeger, 1985], the recommended S(T) and Cp(T) values are in best agreement with the experimental data. With the exception of [ Draeger J.A., 1981], all calculations agree within 1.2 J/mol*K for S(T) and Cp(T). Discrepancy with Cp(1000 K) calculated by [ Draeger J.A., 1981] amounts to 4.7 J/mol*K.; GT
54.98100.
69.79150.
87.00200.
115.7273.15
126.0298.15
126.8300.
167.4400.
203.3500.
233.2600.
258.1700.
278.9800.
296.4900.
311.41000.
324.21100.
335.21200.
344.71300.
352.81400.
359.91500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
163.2 ± 1.7393.Hossenlopp I.A., 1981Please also see Pitzer K.S., 1943, Taylor W.J., 1946.; GT
166.52 ± 0.33398.15
175.82 ± 0.35423.15
178.2 ± 1.7428.
185.40 ± 0.37448.15
189.1 ± 1.7463.
194.17 ± 0.39473.15
202.92 ± 0.41498.15
211.09 ± 0.42523.15

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

Quantity Value Units Method Reference Comment
Δfliquid-24.4 ± 1.0kJ/molCcbProsen, Johnson, et al., 1946ALS
Quantity Value Units Method Reference Comment
Δcliquid-4551.44 ± 0.50kJ/molCmCoops, Mulder, et al., 1946Reanalyzed by Cox and Pilcher, 1970, Original value = -4547.76 ± 0.50 kJ/mol; Corresponding Δfliquid = -25.8 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-4552.86 ± 0.92kJ/molCcbProsen, Johnson, et al., 1946Corresponding Δfliquid = -24.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-4551.7kJ/molCcbRichards and Barry, 1915At 291 K; Corresponding Δfliquid = -25.5 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-4565.9kJ/molCcbRichards and Jesse, 1910At 293 K; Corresponding Δfliquid = -11.3 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid247.154J/mol*KN/AMesserly, Finke, et al., 1988DH
liquid243.51J/mol*KN/APitzer and Scott, 1943DH
liquid253.1J/mol*KN/AHuffman, Parks, et al., 1930Extrapolation below 90 K, 65.19 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
182.219298.15Messerly, Finke, et al., 1988T = 10 to 400 K.; DH
183.65298.15Tardajos, Aicart, et al., 1986DH
181.937298.15Fortier and Benson, 1979DH
181.9298.15Ott, Goates, et al., 1979T = 288.15 to 328.15 K.; DH
181.794298.15Fortier and Benson, 1977DH
181.55298.15Wilhelm, Grolier, et al., 1977DH
181.7298.15Hyder Khan and Subrahmanyam, 1971T = 298; 313 K.; DH
198.7336.Swietoslawski and Zielenkiewicz, 1958Mean value 21 to 106 C.; DH
181.6298.Corruccini and Ginnings, 1947T = 273 to 573 K.; DH
184.9298.Kurbatov, 1947T = 15 to 132 C, mean Cp, three temperatures.; DH
183.76298.15Pitzer and Scott, 1943T = 14 to 360 K.; DH
180.3299.0Huffman, Parks, et al., 1930T = 92 to 299 K. Value is unsmoothed experimental datum.; DH
176.6303.Willams and Daniels, 1924T = 303 to 348 K. Equation only.; DH

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+ + p-Xylene = (C3H9Si+ • p-Xylene)

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

Quantity Value Units Method Reference Comment
Δr118.kJ/molPHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr147.J/mol*KN/AWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
49.4468.PHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

C8H9- + Hydrogen cation = p-Xylene

By formula: C8H9- + H+ = C8H10

Quantity Value Units Method Reference Comment
Δr1598. ± 10.kJ/molG+TSBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Δr1568. ± 9.6kJ/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B

C6H7N+ + p-Xylene = (C6H7N+ • p-Xylene)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr59.4kJ/molPHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; M
Quantity Value Units Method Reference Comment
Δr110.J/mol*KPHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
24.322.PHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; M

C8H10+ + p-Xylene = (C8H10+ • p-Xylene)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr65.3kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; M
Quantity Value Units Method Reference Comment
Δr130.J/mol*KPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; M

C9H12+ + p-Xylene = (C9H12+ • p-Xylene)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr62.3kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; M
Quantity Value Units Method Reference Comment
Δr120.J/mol*KPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; M

Chlorine anion + p-Xylene = (Chlorine anion • p-Xylene)

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

Quantity Value Units Method Reference Comment
Δr16.3kJ/molTDEqFrench, Ikuta, et al., 1982gas phase; B

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
16.300.PHPMSFrench, Ikuta, et al., 1982gas phase; M

(Chromium ion (1+) • p-Xylene) + p-Xylene = (Chromium ion (1+) • 2p-Xylene)

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

Quantity Value Units Method Reference Comment
Δr212. ± 29.kJ/molRAKLin and Dunbar, 1997RCD

Chromium ion (1+) + p-Xylene = (Chromium ion (1+) • p-Xylene)

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

Quantity Value Units Method Reference Comment
Δr180. ± 19.kJ/molRAKLin and Dunbar, 1997RCD

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry 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]

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]

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, Reaction thermochemistry data, References