Home Symbol which looks like a small house Up Solid circle with an upward pointer in it

Heptanoic acid

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Phase change data

Go To: Top, 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:
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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil495. ± 3.KAVGN/AAverage of 23 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus266.0KN/AAdriaanse, Dekker, et al., 1964Uncertainty assigned by TRC = 0.05 K; TRC
Tfus265.6900KN/ABilterys and Gisseleire, 1935Uncertainty assigned by TRC = 0.3 K; TRC
Tfus266.KN/ATimmermans, 1935Uncertainty assigned by TRC = 2. K; TRC
Tfus263.KN/ALumsden, 1905Uncertainty assigned by TRC = 2. K; TRC
Tfus264.KN/AGartenmeister, 1886Uncertainty assigned by TRC = 2. K; TRC
Quantity Value Units Method Reference Comment
Ttriple265.83KN/ASchaake, van Miltenburg, et al., 1982Uncertainty assigned by TRC = 0.02 K; TRC
Quantity Value Units Method Reference Comment
Tc677.8KN/AAndereya and Chase, 1990Uncertainty assigned by TRC = 2. K; TRC
Tc679.KN/AAmbrose and Ghiassee, 1987Uncertainty assigned by TRC = 1. K; TRC
Tc683.52KN/AD'Souza and Teja, 1987Uncertainty assigned by TRC = 3. K; Ambrose's procedure; TRC
Quantity Value Units Method Reference Comment
Pc31.61barN/AAndereya and Chase, 1990Uncertainty assigned by TRC = 0.80 bar; TRC
Pc28.80barN/AAmbrose and Ghiassee, 1987Uncertainty assigned by TRC = 1.00 bar; TRC
Pc28.2963barN/AD'Souza and Teja, 1987Uncertainty assigned by TRC = 0.90 bar; Ambrose's procedure; TRC
Quantity Value Units Method Reference Comment
Deltavap72.9 ± 0.8kJ/molGSVerevkin, 2000Based on data from 283. - 328. K.; AC
Deltavap75.7kJ/molCGCChickos, Hosseini, et al., 1995Based on data from 353. - 393. K.; AC
Deltavap72.0 ± 1.5kJ/molVKruif and Oonk, 1979ALS
Deltavap72.0 ± 1.5kJ/molTEKruif and Oonk, 1979Based on data from 271. - 291. K.; AC

Reduced pressure boiling point

Tboil (K) Pressure (bar) Reference Comment
389.20.015Weast and Grasselli, 1989BS

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
69.0428.N/AClifford, Ramjugernath, et al., 2004Based on data from 413. - 453. K.; AC
72.5 ± 0.8306.GSVerevkin, 2000Based on data from 283. - 328. K.; AC
68.3366.AStephenson and Malanowski, 1987Based on data from 351. - 495. K. See also Stull, 1947.; AC
76.0266.N/Ade Kruif, Schaake, et al., 1982AC

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Temperature (K) A B C Reference Comment
351. - 494.74.306911536.114-137.446Stull, 1947Coefficents calculated by NIST from author's data.
385.8 - 422.71.99576532.776-248.713Kahlbaum, 1894Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
15.44265.8Domalski and Hearing, 1996See also Labban and Westrum, 1991.; AC

Enthalpy of phase transition

DeltaHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
2.1634219.99crystaline, IIcrystaline, ILabban and Westrum, 1991DH
15.1299265.98crystaline, IliquidLabban and Westrum, 1991DH
2.038224.8crystaline, IIcrystaline, ISchaake, van Miltenburg, et al., 1982, 2DH
15.437265.83crystaline, IliquidSchaake, van Miltenburg, et al., 1982, 2DH

Entropy of phase transition

DeltaStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
9.412219.99crystaline, IIcrystaline, ILabban and Westrum, 1991DH
57.295265.98crystaline, IliquidLabban and Westrum, 1991DH
9.07224.8crystaline, IIcrystaline, ISchaake, van Miltenburg, et al., 1982, 2DH
58.07265.83crystaline, IliquidSchaake, van Miltenburg, et al., 1982, 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:


References

Go To: Top, Phase change data, Notes

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

Adriaanse, Dekker, et al., 1964
Adriaanse, N.; Dekker, H.; Coops, J., Some Physical Constants of Normal, Saturated Fatty Acids and Their Methyl Esters, Recl. Trav. Chim. Pays-Bas, 1964, 83, 557. [all data]

Bilterys and Gisseleire, 1935
Bilterys, R.; Gisseleire, J., Investigations on the Congelation Temperature of Organic Compounds, Bull. Soc. Chim. Belg., 1935, 44, 567. [all data]

Timmermans, 1935
Timmermans, J., Researches in Stoichiometry. I. The Heat of Fusion of Organic Compounds., Bull. Soc. Chim. Belg., 1935, 44, 17-40. [all data]

Lumsden, 1905
Lumsden, J.S., The physical properties of heptoic, hexahydrobenzoic, and benzoic acids and their derivatives, J. Chem. Soc., 1905, 87, 90-98. [all data]

Gartenmeister, 1886
Gartenmeister, R., Investigation of the physical characterstics of liquid compounds: vi boiling point and specific volume of normal fatty acid esters, Justus Liebigs Ann. Chem., 1886, 233, 249-315. [all data]

Schaake, van Miltenburg, et al., 1982
Schaake, R.C.F.; van Miltenburg, J.C.; De Kruif, C.G., Thermodynamic properties of the normal alkanoic acids. I. Molar heat capacities of seven odd-numbered normal alkanoic acids., J. Chem. Thermodyn., 1982, 14, 763. [all data]

Andereya and Chase, 1990
Andereya, E.; Chase, J.D., Chem. Eng. Technol., 1990, 13, 304-12. [all data]

Ambrose and Ghiassee, 1987
Ambrose, D.; Ghiassee, N.B., Vapor Pressures and Critical Temperatures and Critical Pressures of Some Alkanoic Acids: C1 to C10, J. Chem. Thermodyn., 1987, 19, 505. [all data]

D'Souza and Teja, 1987
D'Souza, R.; Teja, A.S., The prediction of the vapor pressures of carboxylic acids, Chem. Eng. Commun., 1987, 61, 13. [all data]

Verevkin, 2000
Verevkin, S.P., Measurement and Prediction of the Monocarboxylic Acids Thermochemical Properties, J. Chem. Eng. Data, 2000, 45, 5, 953-960, https://doi.org/10.1021/je990282m . [all data]

Chickos, Hosseini, et al., 1995
Chickos, James S.; Hosseini, Sarah; Hesse, Donald G., Determination of vaporization enthalpies of simple organic molecules by correlations of changes in gas chromatographic net retention times, Thermochimica Acta, 1995, 249, 41-62, https://doi.org/10.1016/0040-6031(95)90670-3 . [all data]

Kruif and Oonk, 1979
Kruif, C.G.; Oonk, H.A.J., Enthalpies of vaporization and vapour pressures of seven aliphatic carboxylic acids, J. Chem. Thermodyn., 1979, 11, 287-290. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Clifford, Ramjugernath, et al., 2004
Clifford, Scott L.; Ramjugernath, Deresh; Raal, J. David, Subatmospheric Vapor Pressure Curves for Propionic Acid, Butyric Acid, Isobutyric Acid, Valeric Acid, Isovaleric Acid, Hexanoic Acid, and Heptanoic Acid, J. Chem. Eng. Data, 2004, 49, 5, 1189-1192, https://doi.org/10.1021/je034180e . [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]

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]

de Kruif, Schaake, et al., 1982
de Kruif, C.G.; Schaake, R.C.F.; van Miltenburg, J.C.; van der Klauw, K.; Blok, J.G., Thermodynamic properties of the normal alkanoic acids III. Enthalpies of vaporization and vapour pressures of 13 normal alkanoic acids, The Journal of Chemical Thermodynamics, 1982, 14, 8, 791-798, https://doi.org/10.1016/0021-9614(82)90176-8 . [all data]

Kahlbaum, 1894
Kahlbaum, G.W.A., Studien uber Dampfspannkraftsmessungen, Z. Phys. Chem. (Leipzig), 1894, 13, 14-55. [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]

Labban and Westrum, 1991
Labban, A.K.; Westrum, E.F., Heat capacity and thermophysical properties of n-heptanoic acid from 5 to 350 K, Can. J. Chem., 1991, 69(11), 1796-1803. [all data]

Schaake, van Miltenburg, et al., 1982, 2
Schaake, R.C.F.; van Miltenburg, J.C.; De Kruif, C.G., Thermodynamic properties of the normal alkanoic acids. I. Molar heat capacities of seven odd-numbered normal alkanoic acids, J. Chem. Thermodynam., 1982, 14, 763-769. [all data]


Notes

Go To: Top, Phase change data, References