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

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

Quantity Value Units Method Reference Comment
Tboil411.4 ± 0.5KAVGN/AAverage of 59 out of 65 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus286.3 ± 0.2KAVGN/AAverage of 18 out of 21 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple286.400KN/AMesserly, Finke, et al., 1988Uncertainty assigned by TRC = 0.01 K; TRC
Ttriple286.3KN/AHuffman, Parks, et al., 1930Uncertainty assigned by TRC = 0.3 K; TRC
Quantity Value Units Method Reference Comment
Tc617. ± 3.KAVGN/AAverage of 12 values; Individual data points
Quantity Value Units Method Reference Comment
Pc35. ± 2.barAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Vc0.378l/molN/ATsonopoulos and Ambrose, 1995 
Quantity Value Units Method Reference Comment
ρc2.65 ± 0.02mol/lN/ATsonopoulos and Ambrose, 1995 
ρc2.661mol/lN/AAkhundov and Imanov, 1970Uncertainty assigned by TRC = 0.05 mol/l; TRC
ρc2.644mol/lN/ASimon, 1957Uncertainty assigned by TRC = 0.04 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap42. ± 4.kJ/molAVGN/AAverage of 14 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
35.67411.5N/AMajer and Svoboda, 1985 
40.3353.N/AHossenlopp and Archer, 1988AC
37.3426.AStephenson and Malanowski, 1987Based on data from 411. to 463. K.; AC
36.1475.AStephenson and Malanowski, 1987Based on data from 460. to 553. K.; AC
36.2566.AStephenson and Malanowski, 1987Based on data from 551. to 616. K.; AC
42.4301.IP,EBStephenson and Malanowski, 1987Based on data from 286. to 453. K. See also Osborn and Douslin, 1974.; AC
36.0 ± 0.1411.CNatarajan and Viswanath, 1985AC
34.5 ± 0.1436.CNatarajan and Viswanath, 1985AC
30.5 ± 0.1484.CNatarajan and Viswanath, 1985AC
24.7 ± 0.1540.CNatarajan and Viswanath, 1985AC
37.3395.N/ACastellari, Francesconi, et al., 1982Based on data from 380. to 410. K.; AC
41.6318.N/AGaw and Swinton, 1968Based on data from 303. to 343. K.; AC
40.1347.MMWillingham, Taylor, et al., 1945Based on data from 332. to 413. K. See also Forziati, Norris, et al., 1949.; AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kJ/mol) β Tc (K) Reference Comment
298. to 440.58.210.2768616.2Majer and Svoboda, 1985 

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
286.43 to 452.384.145531474.403-55.377Osborn and Douslin, 1974Coefficents calculated by NIST from author's data.
420.00 to 600.004.509441788.91-13.902Ambrose, Broderick, et al., 1967Coefficents calculated by NIST from author's data.
331.44 to 412.444.111381450.688-58.16Williamham, Taylor, et al., 1945 
298. to 333.4.448891644.214-40.229Pitzer and Scott, 1943Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
59.4271.N/AStephenson and Malanowski, 1987Based on data from 247. to 286. K. See also Osborn and Douslin, 1974.; AC
60.8286.BHessler and Lichtenstein, 1986AC

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
17.11746286.405Messerly, Finke, et al., 1988, 2DH
17.100286.3Corruccini and Ginnings, 1947DH
17.113286.39Pitzer and Scott, 1943DH
17.11286.3Domalski and Hearing, 1996AC
16.933286.3Huffman, Parks, et al., 1930, 2DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
59.77286.405Messerly, Finke, et al., 1988, 2DH
59.73286.3Corruccini and Ginnings, 1947DH
59.75286.39Pitzer and Scott, 1943DH
59.14286.3Huffman, Parks, et al., 1930, 2DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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

Henry's Law data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry 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 by: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
0.133800.LN/A 
0.174500.MN/A 
0.123000.XN/A 
0.16 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.125300.XN/A 
0.133500.XN/A 
0.14 LN/A 
0.16 VN/A 
0.235400.MN/A 
0.16 VBohon and Claussen, 1951 

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law 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]

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. Thermodyn., 1988, 20, 485. [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, 1547-58. [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]

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]

Hessler and Lichtenstein, 1986
Hessler, W.; Lichtenstein, W., Wiss. Zeitschr. Wilhelm-Pieck-Univ. Rostock, Naturwiss. Reihe, 1986, 35, 7, 27. [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. Thermodynam., 1988, 20, 485-501. [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]

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]

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, 1547-1558. [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]

Bohon and Claussen, 1951
Bohon, R.L.; Claussen, W.F., The solubility of aromatic hydrocarbons in water, J. Am. Chem. Soc., 1951, 73, 1571-1578. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, References