Hexane, 2,5-dimethyl-

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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-260.5 ± 1.5kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcliquid-5460.1 ± 1.4kJ/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -260.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-5435.9kJ/molCcbFajans, 1920Corresponding Δfliquid = -285. kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-5266.2kJ/molCcbRichards and Jesse, 1910At 293 K; Corresponding Δfliquid = -454.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
249.20298.15Osborne and Ginnings, 1947T = 278 to 318 K.; 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Tboil382.1 ± 0.9KAVGN/AAverage of 39 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus182. ± 2.KAVGN/AAverage of 19 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple181.960KN/AAnonymous, 1957Uncertainty assigned by TRC = 0.04 K; TRC
Ttriple181.970KN/AAnonymous, 1957Uncertainty assigned by TRC = 0.02 K; TRC
Ttriple181.960KN/AAnonymous, 1957Uncertainty assigned by TRC = 0.04 K; TRC
Quantity Value Units Method Reference Comment
Tc550.0 ± 0.5KN/ADaubert, 1996 
Tc549.99KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Tc550.0KN/AYoung, 1910Uncertainty assigned by TRC = 0.5 K; TRC
Tc544.0KN/APawlewski, 1883Uncertainty assigned by TRC = 8. K; TRC
Quantity Value Units Method Reference Comment
Pc24.9 ± 0.2barN/ADaubert, 1996 
Pc24.867barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Pc24.878barN/AYoung, 1910Uncertainty assigned by TRC = 0.20 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.482l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.07 ± 0.02mol/lN/ADaubert, 1996 
ρc2.07mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.04 mol/l; TRC
ρc2.071mol/lN/AYoung, 1910Uncertainty assigned by TRC = 0.02 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap37.92kJ/molN/AMajer and Svoboda, 1985 
Δvap37.9kJ/molN/AReid, 1972AC
Δvap37.9 ± 0.1kJ/molCOsborne and Ginnings, 1947, 2AC
Δvap37.85kJ/molCOsborne and Ginnings, 1947ALS
Δvap32.0kJ/molVFajans, 1920ALS

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
32.54382.3N/AMajer and Svoboda, 1985 
36.9322.A,MMStephenson and Malanowski, 1987Based on data from 307. to 383. K. See also Willingham, Taylor, et al., 1945.; AC
41.1261.N/AStull, 1947Based on data from 246. to 382. K.; AC

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
246.5 to 382.33.980211284.664-59.032Stull, 1947Coefficents calculated by NIST from author's data.

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:


Henry's Law 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 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
0.00030 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.

Gas phase ion energetics 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 by: Sharon G. Lias and Joel F. Liebman

Ionization energy determinations

IE (eV) Method Reference
9.76ESTLuo and Pacey, 1992

References

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

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

Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D., Heats of combustion and formation of the paraffin hydrocarbons at 25° C, J. Res. NBS, 1945, 263-267. [all data]

Fajans, 1920
Fajans, K., Die Energie der Atombindungen im Diamanten und in aliphatischen Kohlenwasserstoffen, Ber., 1920, 53, 643-665. [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]

Osborne and Ginnings, 1947
Osborne, N.S.; Ginnings, D.C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. Res. NBS, 1947, 39, 453-477. [all data]

Anonymous, 1957
Anonymous, R., , Am. Pet. Inst. Res. Proj. 6, Carnegie-Mellon Univ., 1957. [all data]

Daubert, 1996
Daubert, T.E., Vapor-Liquid Critical Properties of Elements and Compounds. 5. Branched Alkanes and Cycloalkanes, J. Chem. Eng. Data, 1996, 41, 365-372. [all data]

McMicking and Kay, 1965
McMicking, J.H.; Kay, W.B., Vapor Pressures and Saturated Liquid and Vapor Densities of The Isomeric Heptanes and Isomeric Octanes, Proc., Am. Pet. Inst., Sect. 3, 1965, 45, 75-90. [all data]

Young, 1910
Young, S., The Internal Heat of Vaporization constants of thirty pure substances, Sci. Proc. R. Dublin Soc., 1910, 12, 374. [all data]

Pawlewski, 1883
Pawlewski, B., Critical temperatures of some liquids, Ber. Dtsch. Chem. Ges., 1883, 16, 2633-36. [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]

Reid, 1972
Reid, Robert C., Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00, AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637 . [all data]

Osborne and Ginnings, 1947, 2
Osborne, Nathan S.; Ginnings, Defoe C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. RES. NATL. BUR. STAN., 1947, 39, 5, 453-17, https://doi.org/10.6028/jres.039.031 . [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]

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]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D., Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes, Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]


Notes

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