p-Xylene

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Gas phase thermochemistry data

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

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

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

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., 1988, 2Uncertainty assigned by TRC = 0.01 K; TRC
Ttriple286.3KN/AHuffman, Parks, et al., 1930, 2Uncertainty 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., 1988DH
17.100286.3Corruccini and Ginnings, 1947DH
17.113286.39Pitzer and Scott, 1943DH
17.11286.3Domalski and Hearing, 1996AC
16.933286.3Huffman, Parks, et al., 1930DH

Entropy of fusion

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

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

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

Gas phase ion energetics data

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

Quantity Value Units Method Reference Comment
IE (evaluated)8.44 ± 0.05eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)794.4kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity766.8kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Reference Comment
0.001519 ± 0.000087Hammer, Diri, et al., 2003B

Proton affinity at 298K

Proton affinity (kJ/mol) Reference Comment
793.7Aue, Guidoni, et al., 2000Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM
790.5 ± 1.1Fernandez, Jennings, et al., 1989T = 370 - 750K; Reference Sprot(CH3)2O = 16.5 J/mol K in Hunter and Lias, 1998 needs to be re-evaluated; MM

Gas basicity at 298K

Gas basicity (review) (kJ/mol) Reference Comment
766.9Aue, Guidoni, et al., 2000Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM
771.3 ± 1.4Fernandez, Jennings, et al., 1989T = 370 - 750K; Reference Sprot(CH3)2O = 16.5 J/mol K in Hunter and Lias, 1998 needs to be re-evaluated; MM

Protonation entropy at 298K

Protonation entropy (J/mol*K) Reference Comment
44.2Fernandez, Jennings, et al., 1989T = 370 - 750K; Reference Sprot(CH3)2O = 16.5 J/mol K in Hunter and Lias, 1998 needs to be re-evaluated; MM

Ionization energy determinations

IE (eV) Method Reference Comment
8.52 ± 0.01EQLias and Ausloos, 1978LLK
8.44PEBock, Kaim, et al., 1978LLK
8.80 ± 0.05EILoudon and Mazengo, 1974LLK
8.37 ± 0.02PEMaier and Turner, 1973LLK
8.52CTSKinoshita, 1962RDSH
8.445PIBralsford, Harris, et al., 1960RDSH
8.44 ± 0.02PIVilesov and Terenin, 1957RDSH
8.445 ± 0.015PIWatanabe, 1954RDSH
8.48SHammond, Price, et al., 1950RDSH
8.44PEHowell, Goncalves, et al., 1984Vertical value; LBLHLM
8.43PEKoenig, Tuttle, et al., 1974Vertical value; LLK
8.6 ± 0.03PEKlessinger, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H5+16.3 ± 0.2C2H2+CH3EITajima and Tsuchiya, 1973LLK
C7H7+11.5 ± 0.3?EIMcLafferty and Winkler, 1974LLK
C7H7+11.9 ± 0.2CH3EILoudon and Mazengo, 1974LLK
C7H7+11.05 ± 0.05CH3PIAkopyan and Vilesov, 1968RDSH
C7H7+11.3 ± 0.1CH3EINounou, 1966RDSH
C8H9+12.1 ± 0.2HEILoudon and Mazengo, 1974LLK
C8H9+11.35 ± 0.05HPIAkopyan and Vilesov, 1968RDSH
C8H9+11.9 ± 0.1HEITait, Shannon, et al., 1962RDSH

De-protonation reactions

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

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics 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:
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+ + 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

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 = (Chromium ion (1+) • p-Xylene)

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

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

(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

References

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

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
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Notes

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