Heneicosane
- Formula: C21H44
- Molecular weight: 296.5741
- IUPAC Standard InChIKey: FNAZRRHPUDJQCJ-UHFFFAOYSA-N
- CAS Registry Number: 629-94-7
- 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-Heneicosane; n-henicosane; henicosane
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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 liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
159.3 | 315.93 | Grigor'ev and Andolenko, 1984 | T = 316 to 433 K. Unsmoothed experimental datum given as 2.247 kJ/kg*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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 629.7 | K | N/A | Weast and Grasselli, 1989 | BS |
Tboil | 635.1 | K | N/A | Ivanov, Ivanov, et al., 1954 | Uncertainty assigned by TRC = 1.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 313.4 ± 0.7 | K | AVG | N/A | Average of 16 out of 17 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 778. ± 8. | K | N/A | Ambrose and Tsonopoulos, 1995 | |
Tc | 777.6 | K | N/A | Nikitin, Pavlov, et al., 1994 | Uncertainty assigned by TRC = 3. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 10. ± 2. | atm | N/A | Ambrose and Tsonopoulos, 1995 | |
Pc | 10.17 | atm | N/A | Nikitin, Pavlov, et al., 1994 | Uncertainty assigned by TRC = 0.39 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 25.53 | kcal/mol | CGC | Chickos and Hanshaw, 2004 | Based on data from 434. to 539. K.; AC |
ΔvapH° | 26.15 ± 0.62 | kcal/mol | CGC | Chickos and Wilson, 1997 | AC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 33.9 ± 2.4 | kcal/mol | B | Piacente, Pompili, et al., 1991 | AC |
Reduced pressure boiling point
Tboil (K) | Pressure (atm) | Reference | Comment |
---|---|---|---|
373.2 | 0.003 | Aldrich Chemical Company Inc., 1990 | BS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
22.4 | 368. | N/A | Sawaya, Mokbel, et al., 2006 | Based on data from 351. to 462. K.; AC |
26.3 ± 0.5 | 382. | TE | Piacente, Fontana, et al., 1994 | Based on data from 365. to 400. K.; AC |
20.2 | 367. | TE,ME,GS | Piacente, Pompili, et al., 1991 | Based on data from 352. to 478. K.; AC |
21.1 | 437. | A,EST | Stephenson and Malanowski, 1987 | Based on data from 422. to 630. 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 |
---|---|---|---|---|---|
425.8 to 623.7 | 5.91502 | 3571.218 | -19.953 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
11.1 | 313. | DSC | Mondieig, Rajabalee, et al., 2004 | AC |
11.4 | 313.7 | N/A | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
12.11 | 305.7 | Domalski and Hearing, 1996 | CAL |
36.343 | 313.7 |
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.
Grigor'ev and Andolenko, 1984
Grigor'ev, B.A.; Andolenko, R.A.,
Investigation of the isobaric heat capacity of n-paraffinic hydrocarbons at atmospheric pressure, Izv. Vyssh. Ucheb. Zaved.,
Neft i Gaz, 1984, (2), 60-62. [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]
Ivanov, Ivanov, et al., 1954
Ivanov, D.; Ivanov, Ch.; Stoianova-Ivanova, B.,
Composistion of Stearoptene from Bulgarian Rose Oil. II. Saturated Hydrocarbons Other Than Eicosane,
Dokl. Bolg. Akad. Nauk, 1954, 7, 17-20. [all data]
Ambrose and Tsonopoulos, 1995
Ambrose, D.; Tsonopoulos, C.,
Vapor-Liquid Critical Properties of Elements and Compounds. 2. Normal Alkenes,
J. Chem. Eng. Data, 1995, 40, 531-546. [all data]
Nikitin, Pavlov, et al., 1994
Nikitin, E.D.; Pavlov, P.A.; Bessonova, N.V.,
Critical constants of n-alkanes with from 17 to 24 carbon atoms,
J. Chem. Thermodyn., 1994, 26, 177-82. [all data]
Chickos and Hanshaw, 2004
Chickos, James S.; Hanshaw, William,
Vapor Pressures and Vaporization Enthalpies of the n -Alkanes from C 21 to C 30 at T = 298.15 K by Correlation Gas Chromatography,
J. Chem. Eng. Data, 2004, 49, 1, 77-85, https://doi.org/10.1021/je0301747
. [all data]
Chickos and Wilson, 1997
Chickos, James S.; Wilson, Joe A.,
Vaporization Enthalpies at 298.15 K of the n -Alkanes from C 21 to C 28 and C 30,
J. Chem. Eng. Data, 1997, 42, 1, 190-197, https://doi.org/10.1021/je960089h
. [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]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]
Sawaya, Mokbel, et al., 2006
Sawaya, Terufat; Mokbel, Ilham; Ainous, Nédal; Rauzy, Evelyne; Berro, Charles; Jose, Jacques,
Experimental Vapor Pressures of Six n -Alkanes (C 21 , C 23 , C 25 , C 27 , C 29 , C 30 ) in the Temperature Range between 350 K and 460 K,
J. Chem. Eng. Data, 2006, 51, 3, 854-858, https://doi.org/10.1021/je050182i
. [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]
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]
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]
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]
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]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔsubH° Enthalpy of sublimation at standard conditions 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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