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Octane

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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:
DRB - Donald R. Burgess, Jr.
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
Deltafgas-49.88kcal/molN/AGood, 1972Value computed using «DELTA»fHliquid° value of -250.3±1.8 kj/mol from Good, 1972 and «DELTA»vapH° value of 41.6 kj/mol from Prosen and Rossini, 1945.; DRB
Deltafgas-49.82 ± 0.16kcal/molCcbProsen and Rossini, 1945see Prosen and Rossini, 1944; ALS
Quantity Value Units Method Reference Comment
gas111.63 ± 0.22cal/mol*KN/AScott D.W., 1974This reference does not contain the original experimental data. Experimental entropy value is based on the results [ Messerly J.F., 1967] for S(liquid).; GT

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
55.63 ± 0.11385.65Hossenlopp I.A., 1981Please also see Barrow G.M., 1951.; GT
57.11 ± 0.11398.15
58.000405.7
59.89 ± 0.12423.15
62.86 ± 0.13448.15
64.699462.5
65.69 ± 0.13473.15
68.35 ± 0.14498.15
70.600522.7
70.98 ± 0.14523.15

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
34.601200.Scott D.W., 1974, 2Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, Scott D.W., 1974, 2]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1944, Pitzer K.S., 1946].; GT
41.991273.15
44.88 ± 0.1298.15
45.100300.
57.299400.
68.549500.
78.100600.
86.099700.
92.801800.
98.401900.
103.101000.
107.201100.
110.701200.
114.001300.
117.001400.
119.001500.

References

Go To: Top, Gas phase thermochemistry data, Notes

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

Good, 1972
Good, W.D., The enthalpies of combustion and formation of n-octane and 2,2,3,3-tetramethylbutane, J. Chem. Thermodyn., 1972, 4, 709-714. [all data]

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]

Prosen and Rossini, 1944
Prosen, E.J.; Rossini, F.D., Heats of combustion of eight normal paraffin hydrocarbons in the liquid state, J. Res. NBS, 1944, 33, 255-272. [all data]

Scott D.W., 1974
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [all data]

Messerly J.F., 1967
Messerly J.F., Low-temperature thermal data for n-pentane, n-heptadecane, and n-octadecane. Revised thermodynamic functions for the n-alkanes, C5-C18, J. Chem. Eng. Data, 1967, 12, 338-346. [all data]

Hossenlopp I.A., 1981
Hossenlopp I.A., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [all data]

Barrow G.M., 1951
Barrow G.M., Experimental vapor heat capacities and heats of vaporization of seven octanes, J. Am. Chem. Soc., 1951, 73, 1824-1826. [all data]

Scott D.W., 1974, 2
Scott D.W., Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]

Pitzer K.S., 1944
Pitzer K.S., Thermodynamics of gaseous paraffins. Specific heat and related properties, Ind. Eng. Chem., 1944, 36, 829-831. [all data]

Pitzer K.S., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]


Notes

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