Heptacosane
- Formula: C27H56
- Molecular weight: 380.7335
- IUPAC Standard InChIKey: BJQWYEJQWHSSCJ-UHFFFAOYSA-N
- CAS Registry Number: 593-49-7
- 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: n-Heptacosane
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Condensed phase thermochemistry 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: Eugene S. Domalski and Elizabeth D. Hearing
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
198. | 313. | Verdonk, 1938 | crystaline, β phase; Also data for α form, 1117 J/mol*K at 328 K, and liquid, 828 J/mol*K at 338 K. |
Phase change data
Go To: Top, Condensed phase thermochemistry 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
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 332. ± 1. | K | AVG | N/A | Average of 19 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 332. | K | N/A | Schaerer, Busso, et al., 1955 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.1 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 46.8 ± 7.2 | kcal/mol | B | Piacente, Pompili, et al., 1991 | AC |
Reduced pressure boiling point
Tboil (K) | Pressure (atm) | Reference | Comment |
---|---|---|---|
543.2 | 0.020 | Weast and Grasselli, 1989 | BS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
31.5 ± 0.2 | 423. | TE | Piacente, Fontana, et al., 1994 | Based on data from 401. to 441. K.; AC |
22.5 | 523. | ME,TE,GS | Piacente, Pompili, et al., 1991 | Based on data from 508. to 570. K.; AC |
27.94 ± 0.72 | 421. | TE | Pompili and Piacente, 1990 | Based on data from 401. to 441. K.; AC |
24.93 | 488. | A,EST | Stephenson and Malanowski, 1987 | Based on data from 473. to 695. K. See also Kudchadker and Zwolinski, 1966.; AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
351.3 to 434.8 | 6.25052 | 3654.268 | -86.045 | Morecroft, 1964 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
15.0 | 331.6 | DSC | Mondieig, Rajabalee, et al., 2004 | AC |
14.11 | 332.1 | DSC | Lourdin, Roux, et al., 1992 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.70 | 318. | Lourdin, Roux, et al., 1992, 2 | CAL |
19.30 | 325.4 | ||
42.500 | 332.1 |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
6.9199 | 320.25 | crystaline, II | crystaline, I | Schaerer, Busso, et al., 1955, 2 | DH |
14.440 | 331.95 | crystaline, I | liquid | Schaerer, Busso, et al., 1955, 2 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
21.6 | 320.25 | crystaline, II | crystaline, I | Schaerer, Busso, et al., 1955, 2 | DH |
43.50 | 331.95 | crystaline, I | liquid | Schaerer, Busso, et al., 1955, 2 | DH |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Verdonk, 1938
Verdonk, G.,
Calorimetric analysis of paraffins - Contributions to the general subject of "calorimetric analysis" by J. Straub and R.N.M.A. Malataux,
Chem. Weekblad, 1938, 35, 741-743. [all data]
Schaerer, Busso, et al., 1955
Schaerer, A.A.; Busso, C.J.; Smith, A.E.; Skinner, L.B.,
Properties of Pure Normal Alkanes in the C17 to C36 Range,
J. Am. Chem. Soc., 1955, 77, 2017-8. [all data]
Piacente, Pompili, et al., 1991
Piacente, Vincenzo; Pompili, Tiziano; Scardala, Paolo; Ferro, Daniela,
Temperature dependence of the vaporization enthalpies of n-alkanes from vapour-pressure measurements,
The Journal of Chemical Thermodynamics, 1991, 23, 4, 379-396, https://doi.org/10.1016/S0021-9614(05)80092-8
. [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]
Piacente, Fontana, et al., 1994
Piacente, Vincenzo; Fontana, Danilo; Scardala, Paolo,
Enthalpies of Vaporization of a Homologous Series of n-Alkanes Determined from Vapor Pressure Measurements,
J. Chem. Eng. Data, 1994, 39, 2, 231-237, https://doi.org/10.1021/je00014a009
. [all data]
Pompili and Piacente, 1990
Pompili, T.; Piacente, V.,
Enthalpy of vaporization of n-heptacosane and n-nonacosane from their vapour pressure determinations,
Thermochimica Acta, 1990, 170, 289-291, https://doi.org/10.1016/0040-6031(90)80548-D
. [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]
Kudchadker and Zwolinski, 1966
Kudchadker, A.P.; Zwolinski, B.J.,
Vapor Pressure and Boiling Points of Normal Alkanes, C 21 to C 100 .,
J. Chem. Eng. Data, 1966, 11, 2, 253-255, https://doi.org/10.1021/je60029a039
. [all data]
Morecroft, 1964
Morecroft, D.W.,
Vapor Pressures of Some High Molecular Weight Hydrocarbons.,
J. Chem. Eng. Data, 1964, 9, 4, 488-490, https://doi.org/10.1021/je60023a003
. [all data]
Mondieig, Rajabalee, et al., 2004
Mondieig, D.; Rajabalee, F.; Metivaud, V.; Oonk, H.A.J.; Cuevas-Diarte, M.A.,
n -Alkane Binary Molecular Alloys,
Chem. Mater., 2004, 16, 5, 786-798, https://doi.org/10.1021/cm031169p
. [all data]
Lourdin, Roux, et al., 1992
Lourdin, D.; Roux, A.H.; Grolier, J.-P.E.; Buisine, J.-M.,
Thermobarometric and differential scanning calorimetric study of the polymorphism of some even and odd paraffins (C26, C27, C40, C60),
Thermochimica Acta, 1992, 204, 1, 99-110, https://doi.org/10.1016/0040-6031(92)80319-R
. [all data]
Lourdin, Roux, et al., 1992, 2
Lourdin, D.; Roux, A.H.; Grolier, J.-P.E.; Buisine, J.-M.,
Thermobarometric and differential scanning calorimetric study of the polymorphism of some even and odd paraffins (C26, C27, C40, C60),
Thermochim. Acta, 1992, 204, 1, 99, https://doi.org/10.1016/0040-6031(92)80319-R
. [all data]
Schaerer, Busso, et al., 1955, 2
Schaerer, A.A.; Busso, C.J.; Smith, A.E.; Skinner, L.B.,
Properties of pure normal alkanes in the C17 to C36 range,
J. Am. Chem. Soc., 1955, 77, 2017-2019. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid Tboil Boiling point Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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