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Heneicosane

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Condensed phase thermochemistry data

Go To: Top, Phase change data, IR Spectrum, Mass spectrum (electron ionization), 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
159.3315.93Grigor'ev and Andolenko, 1984T = 316 to 433 K. Unsmoothed experimental datum given as 2.247 kJ/kg*K.

Phase change 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:
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
Tboil629.7KN/AWeast and Grasselli, 1989BS
Tboil635.1KN/AIvanov, Ivanov, et al., 1954Uncertainty assigned by TRC = 1.5 K; TRC
Quantity Value Units Method Reference Comment
Tfus313.4 ± 0.7KAVGN/AAverage of 16 out of 17 values; Individual data points
Quantity Value Units Method Reference Comment
Tc778. ± 8.KN/AAmbrose and Tsonopoulos, 1995 
Tc777.6KN/ANikitin, Pavlov, et al., 1994Uncertainty assigned by TRC = 3. K; TRC
Quantity Value Units Method Reference Comment
Pc10. ± 2.atmN/AAmbrose and Tsonopoulos, 1995 
Pc10.17atmN/ANikitin, Pavlov, et al., 1994Uncertainty assigned by TRC = 0.39 atm; TRC
Quantity Value Units Method Reference Comment
Deltavap25.53kcal/molCGCChickos and Hanshaw, 2004Based on data from 434. - 539. K.; AC
Deltavap26.15 ± 0.62kcal/molCGCChickos and Wilson, 1997AC
Quantity Value Units Method Reference Comment
Deltasub33.9 ± 2.4kcal/molBPiacente, Pompili, et al., 1991AC

Reduced pressure boiling point

Tboil (K) Pressure (atm) Reference Comment
373.20.003Aldrich Chemical Company Inc., 1990BS

Enthalpy of vaporization

DeltavapH (kcal/mol) Temperature (K) Method Reference Comment
22.4368.N/ASawaya, Mokbel, et al., 2006Based on data from 351. - 462. K.; AC
26.3 ± 0.5382.TEPiacente, Fontana, et al., 1994Based on data from 365. - 400. K.; AC
20.2367.TE,ME,GSPiacente, Pompili, et al., 1991Based on data from 352. - 478. K.; AC
21.1437.A,ESTStephenson and Malanowski, 1987Based on data from 422. - 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 - 623.75.915023571.218-19.953Stull, 1947Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kcal/mol) Temperature (K) Method Reference Comment
11.1313.DSCMondieig, Rajabalee, et al., 2004AC
11.4313.7N/ADomalski and Hearing, 1996AC

Entropy of fusion

DeltafusS (cal/mol*K) Temperature (K) Reference Comment
12.11305.7Domalski and Hearing, 1996CAL
36.343313.7

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:


IR Spectrum

Go To: Top, Condensed phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Gas Phase Spectrum

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IR spectrum
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Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

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Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center
State gas
Instrument HP-GC/MS/IRD

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


Mass spectrum (electron ionization)

Go To: Top, Condensed phase thermochemistry data, Phase change data, IR Spectrum, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

View image of digitized spectrum (can be printed in landscape orientation).

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Download spectrum in JCAMP-DX format.

Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-2012
NIST MS number 230947

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


References

Go To: Top, Condensed phase thermochemistry data, Phase change data, IR Spectrum, Mass spectrum (electron ionization), 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, IR Spectrum, Mass spectrum (electron ionization), References