Heptanoic acid
- Formula: C7H14O2
- Molecular weight: 130.1849
- IUPAC Standard InChIKey: MNWFXJYAOYHMED-UHFFFAOYSA-N
- CAS Registry Number: 111-14-8
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Enanthic acid; n-Heptanoic acid; n-Heptoic acid; n-Heptylic acid; Enanthylic acid; Heptoic acid; Heptylic acid; Oenanthic acid; Oenanthylic acid; 1-Hexanecarboxylic acid; Hepthlic acid; Hexacid C-7; 1-Heptanoic acid; NSC 2192
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Phase change data
Go To: Top, 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:
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 |
---|---|---|---|---|---|
Tboil | 495. ± 3. | K | AVG | N/A | Average of 23 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 266.0 | K | N/A | Adriaanse, Dekker, et al., 1964 | Uncertainty assigned by TRC = 0.05 K; TRC |
Tfus | 265.6900 | K | N/A | Bilterys and Gisseleire, 1935 | Uncertainty assigned by TRC = 0.3 K; TRC |
Tfus | 266. | K | N/A | Timmermans, 1935 | Uncertainty assigned by TRC = 2. K; TRC |
Tfus | 263. | K | N/A | Lumsden, 1905 | Uncertainty assigned by TRC = 2. K; TRC |
Tfus | 264. | K | N/A | Gartenmeister, 1886 | Uncertainty assigned by TRC = 2. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 265.83 | K | N/A | Schaake, van Miltenburg, et al., 1982 | Uncertainty assigned by TRC = 0.02 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 677.8 | K | N/A | Andereya and Chase, 1990 | Uncertainty assigned by TRC = 2. K; TRC |
Tc | 679. | K | N/A | Ambrose and Ghiassee, 1987 | Uncertainty assigned by TRC = 1. K; TRC |
Tc | 683.52 | K | N/A | D'Souza and Teja, 1987 | Uncertainty assigned by TRC = 3. K; Ambrose's procedure; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 31.61 | bar | N/A | Andereya and Chase, 1990 | Uncertainty assigned by TRC = 0.80 bar; TRC |
Pc | 28.80 | bar | N/A | Ambrose and Ghiassee, 1987 | Uncertainty assigned by TRC = 1.00 bar; TRC |
Pc | 28.2963 | bar | N/A | D'Souza and Teja, 1987 | Uncertainty assigned by TRC = 0.90 bar; Ambrose's procedure; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 72.9 ± 0.8 | kJ/mol | GS | Verevkin, 2000 | Based on data from 283. to 328. K.; AC |
ΔvapH° | 75.7 | kJ/mol | CGC | Chickos, Hosseini, et al., 1995 | Based on data from 353. to 393. K.; AC |
ΔvapH° | 72.0 ± 1.5 | kJ/mol | V | Kruif and Oonk, 1979 | ALS |
ΔvapH° | 72.0 ± 1.5 | kJ/mol | TE | Kruif and Oonk, 1979 | Based on data from 271. to 291. K.; AC |
Reduced pressure boiling point
Tboil (K) | Pressure (bar) | Reference | Comment |
---|---|---|---|
389.2 | 0.015 | Weast and Grasselli, 1989 | BS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
69.0 | 428. | N/A | Clifford, Ramjugernath, et al., 2004 | Based on data from 413. to 453. K.; AC |
72.5 ± 0.8 | 306. | GS | Verevkin, 2000 | Based on data from 283. to 328. K.; AC |
68.3 | 366. | A | Stephenson and Malanowski, 1987 | Based on data from 351. to 495. K. See also Stull, 1947.; AC |
76.0 | 266. | N/A | de Kruif, Schaake, et al., 1982 | 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 |
---|---|---|---|---|---|
351. to 494.7 | 4.30691 | 1536.114 | -137.446 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
385.8 to 422.7 | 1.99576 | 532.776 | -248.713 | Kahlbaum, 1894 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
15.44 | 265.8 | Domalski and Hearing, 1996 | See also Labban and Westrum, 1991.; AC |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
2.1634 | 219.99 | crystaline, II | crystaline, I | Labban and Westrum, 1991 | DH |
15.1299 | 265.98 | crystaline, I | liquid | Labban and Westrum, 1991 | DH |
2.038 | 224.8 | crystaline, II | crystaline, I | Schaake, van Miltenburg, et al., 1982, 2 | DH |
15.437 | 265.83 | crystaline, I | liquid | Schaake, van Miltenburg, et al., 1982, 2 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
9.412 | 219.99 | crystaline, II | crystaline, I | Labban and Westrum, 1991 | DH |
57.295 | 265.98 | crystaline, I | liquid | Labban and Westrum, 1991 | DH |
9.07 | 224.8 | crystaline, II | crystaline, I | Schaake, van Miltenburg, et al., 1982, 2 | DH |
58.07 | 265.83 | crystaline, I | liquid | Schaake, van Miltenburg, et al., 1982, 2 | DH |
Gas phase ion energetics data
Go To: Top, Phase change 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: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C2H4O2+ | 10.54 ± 0.05 | C5H10 | EI | Holmes and Lossing, 1980 | |
C2H4O2+ | 10.54 | 1-C5H10 | EI | Holmes and Lossing, 1980, 2 |
References
Go To: Top, Phase change 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.
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]
Holmes and Lossing, 1980
Holmes, J.L.; Lossing, F.P.,
Thermochemistry and unimolecular reactions of ionized acetic acid and its enol in the gas phase.,
J. Am. Chem. Soc., 1980, 102, 3732. [all data]
Holmes and Lossing, 1980, 2
Holmes, J.L.; Lossing, F.P.,
Gas-phase heats of formation of keto and enol ions of carbonyl compounds.,
J. Am. Chem. Soc., 1980, 102, 1591. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔfusH Enthalpy of fusion ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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