Heptane

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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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-187.8 ± 0.79kJ/molCcbProsen and Rossini, 1945ALS
Δfgas-189.3kJ/molN/ADavies and Gilbert, 1941Value computed using ΔfHliquid° value of -225.9±1.3 kj/mol from Davies and Gilbert, 1941 and ΔvapH° value of 36.6 kj/mol from Prosen and Rossini, 1945.; DRB

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
127.65200.Scott D.W., 1974Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1944, Pitzer K.S., 1946].; GT
154.64273.15
165.2 ± 0.3298.15
165.98300.
210.66400.
252.09500.
287.44600.
317.15700.
342.25800.
363.59900.
381.581000.
397.061100.
410.451200.
422.581300.
435.141400.
443.501500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
191.50 ± 0.19357.10Waddington G., 1947GT
198.78 ± 0.20373.15
210.75 ± 0.21400.40
225.31 ± 0.23434.35
238.49 ± 0.24466.10

References

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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]

Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C., Heats of combustion and formation of the nine isomeric heptanes in the liquid state, J. Am. Chem. Soc., 1941, 63, 2730-2732. [all data]

Scott D.W., 1974
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]

Scott D.W., 1974, 2
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [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]

Waddington G., 1947
Waddington G., An improved flow calorimeter. Experimental vapor heat capacities and heats of vaporization of n-heptane and 2,2,3-trimethylbutane, J. Am. Chem. Soc., 1947, 69, 22-30. [all data]


Notes

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