Eicosane
- Formula: C20H42
- Molecular weight: 282.5475
- IUPAC Standard InChIKey: CBFCDTFDPHXCNY-UHFFFAOYSA-N
- CAS Registry Number: 112-95-8
- 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: n-Eicosane; n-Icosane; icosane
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Gas phase thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -455.8 ± 3.1 | kJ/mol | Ccb | Prosen and Rossini, 1945 |
Condensed phase thermochemistry 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:
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 |
---|---|---|---|---|---|
ΔfH°liquid | -556.5 ± 3.1 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -13316.4 ± 2.8 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -556.26 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°solid,1 bar | 558.6 | J/mol*K | N/A | Parks, Huffman, et al., 1930 | Extrapolation below 90 K, 64.68 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
664. | 325. | Hoehne, 1981 | T = 300 to 500 K. Cv = 2.32 J/g*K.; DH |
Constant pressure heat capacity of solid
Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
602.5 | 279.1 | Parks, Huffman, et al., 1930 | T = 94 to 280 K. Value is unsmoothed experimental datum.; DH |
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
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 | 616.2 | K | N/A | Weast and Grasselli, 1989 | BS |
Tboil | 582.9 | K | N/A | Tsakalotos, 1906 | Uncertainty assigned by TRC = 5. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 310. ± 1. | K | AVG | N/A | Average of 26 out of 30 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 309.64 | K | N/A | Marsh, 1987 | Uncertainty assigned by TRC = 0.01 K; recommended as fixed point for thermometry; TRC |
Ttriple | 309.7 | K | N/A | Parks, Huffman, et al., 1930, 2 | Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 768. ± 8. | K | N/A | Ambrose and Tsonopoulos, 1995 | |
Tc | 767.5 | K | N/A | Nikitin, Pavlov, et al., 1994 | Uncertainty assigned by TRC = 3. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 11. ± 2. | bar | N/A | Ambrose and Tsonopoulos, 1995 | |
Pc | 10.70 | bar | N/A | Nikitin, Pavlov, et al., 1994 | Uncertainty assigned by TRC = 0.40 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 102. ± 2. | kJ/mol | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 170.4 | kJ/mol | C | Morawetz, 1972 | AC |
Reduced pressure boiling point
Tboil (K) | Pressure (bar) | Reference | Comment |
---|---|---|---|
493.2 | 0.040 | Aldrich Chemical Company Inc., 1990 | BS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
99.5 ± 1.1 | 343. | N/A | Razzouk, Naccoul, et al., 2009 | Based on data from 313. to 373. K.; AC |
78.0 | 448. | N/A | Morgan and Kobayashi, 1994 | Based on data from 433. to 583. K.; AC |
110. ± 2. | 368. | TE | Piacente, Fontana, et al., 1994 | Based on data from 347. to 388. K.; AC |
79.0 | 360. | TE,ME,GS | Piacente, Pompili, et al., 1991 | Based on data from 345. to 470. K.; AC |
80.78 ± 0.07 | 440. | V | Chirico, Nguyen, et al., 1989 | ALS |
80.8 | 440. | EB,IP | Chirico, Nguyen, et al., 1989 | Based on data from 388. to 625. K.; AC |
68.3 | 540. | EB,IP | Chirico, Nguyen, et al., 1989 | Based on data from 388. to 625. K.; AC |
89.6 | 378. | N/A | Sasse, Jose, et al., 1988 | Based on data from 363. to 460. K.; AC |
71.1 | 543. | A | Stephenson and Malanowski, 1987 | Based on data from 528. to 620. K.; AC |
93.3 | 359. | A,GS | Stephenson and Malanowski, 1987 | Based on data from 344. to 380. K. See also Macknick and Prausnitz, 1979.; AC |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
172.8 ± 3.0 | 305. | N/A | Razzouk, Naccoul, et al., 2009 | Based on data from 302. to 308. K.; AC |
179.5 ± 2.0 | 367. | B | Piacente, Fontana, et al., 1994 | AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
69.000 | 309.6 | N/A | Barbillon, Schuffenecker, et al., 1991 | DH |
67.800 | 308.8 | N/A | Kolesnikov and Syunyaev, 1985 | DH |
69.873 | 309.75 | N/A | Company, 1973 | DH |
69.8 | 310.2 | N/A | Khimeche, Boumrah, et al., 2006 | See also Genovese, Amarasinghe, et al., 2006.; AC |
68.1 | 309.7 | DSC | Mondieig, Rajabalee, et al., 2004 | AC |
67.8 | 309.7 | N/A | Domalski and Hearing, 1996 | AC |
70.900 | 308.5 | N/A | Syunyaev, Tumanyan, et al., 1984 | Relative error in determination ± 5%.; DH |
61.476 | 309.7 | N/A | Parks, Huffman, et al., 1930 | DH |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
219.6 | 308.8 | Kolesnikov and Syunyaev, 1985 | DH |
225.6 | 309.75 | Company, 1973 | DH |
229.8 | 308.5 | Syunyaev, Tumanyan, et al., 1984 | Relative; DH |
198.50 | 309.7 | Parks, Huffman, et al., 1930 | DH |
Temperature of phase transition
Ttrs (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|
309.63 | crystaline, α | liquid | Ksiazczak, 1989 | DH |
309.32 | crystaline, β | liquid | Ksiazczak, 1989 | DH |
309.24 | crystaline, α | crystaline, β | Ksiazczak, 1989 | DH |
309.35 | crystaline, II | crystaline, I | Schaerer, Busso, et al., 1955 | DH |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
46.170 | 309.2 | crystaline, II | liquid | Claudy and Letoffe, 1991 | DH |
66.935 | 310.0 | crystaline, I | liquid | Claudy and Letoffe, 1991 | DH |
69.873 | 309.75 | crystaline, I | liquid | Schaerer, Busso, et al., 1955 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
225.6 | 309.75 | crystaline, I | liquid | Schaerer, Busso, et al., 1955 | DH |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
By formula: H2 + C20H40 = C20H42
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -126.9 ± 1.3 | kJ/mol | Chyd | Rogers and Skanupong, 1974 | liquid phase; solvent: Hexane |
IR Spectrum
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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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Gas Phase Spectrum
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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 | Sadtler Research Labs Under US-EPA Contract |
State | gas |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D.,
Heats of combustion and formation of the paraffin hydrocarbons at 25° C,
J. Res. NBS, 1945, 263-267. [all data]
Parks, Huffman, et al., 1930
Parks, G.S.; Huffman, H.M.; Thomas, S.B.,
Thermal data on organic compounds. VI. The heat capacities, entropies and free energies of some saturated, non-benzenoid hydrocarbons,
J. Am. Chem. Soc., 1930, 52, 1032-1041. [all data]
Hoehne, 1981
Hoehne, G.W.H.,
Transitions of n-alkanes above the melting point,
Polym. Bull. (Berlin), 1981, 6, 41-46. [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]
Tsakalotos, 1906
Tsakalotos, D.E.,
C. R. Hebd. Seances Acad. Sci., 1906, 143, 1235. [all data]
Marsh, 1987
Marsh, K.N.,
Recommended Reference Materials for the Realization of Physicochemical Properties, Blackwell Sci. Pub., Oxford, 1987. [all data]
Parks, Huffman, et al., 1930, 2
Parks, G.S.; Huffman, H.M.; Thomas, S.B.,
Thermal Data on Organic Compounds VI. The Heat Capacities, Entropies and Free Energies of Some Saturated, Non-Benzenoid Hydrocarbons,
J. Am. Chem. Soc., 1930, 52, 1032-41. [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]
Morawetz, 1972
Morawetz, Ernst,
Correlation of sublimation enthalpies at 298.15 K with molecular structure for planar aromatic hydrocarbons,
The Journal of Chemical Thermodynamics, 1972, 4, 3, 461-467, https://doi.org/10.1016/0021-9614(72)90030-4
. [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]
Razzouk, Naccoul, et al., 2009
Razzouk, Antonio; Naccoul, Ramy Abou; Mokbel, Ilham; Saab, Joseph; Jose, Jacques,
Vapor and Sublimation Pressures of Three Normal Alkanes: C 20 , C 24 , and C 28,
J. Chem. Eng. Data, 2009, 54, 4, 1214-1219, https://doi.org/10.1021/je800534x
. [all data]
Morgan and Kobayashi, 1994
Morgan, David L.; Kobayashi, Riki,
Direct vapor pressure measurements of ten n-alkanes m the 10-C28 range,
Fluid Phase Equilibria, 1994, 97, 211-242, https://doi.org/10.1016/0378-3812(94)85017-8
. [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]
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]
Chirico, Nguyen, et al., 1989
Chirico, R.D.; Nguyen, A.; Steele, W.V.; Strube, M.M.,
Vapor pressure of n-alkanes revisited. New high-precision vapor pressure data on n-decane, n-eicosane, and n-octacosane,
J. Chem. Eng. Data, 1989, 34, 149-156. [all data]
Sasse, Jose, et al., 1988
Sasse, Karim; Jose, Jacques; Merlin, Jean-Claude,
A static apparatus for measurement of low vapor pressures. Experimental results on high molecular-weight hydrocarbons,
Fluid Phase Equilibria, 1988, 42, 287-304, https://doi.org/10.1016/0378-3812(88)80065-7
. [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]
Macknick and Prausnitz, 1979
Macknick, A. Brian; Prausnitz, John M.,
Vapor pressures of high-molecular-weight hydrocarbons,
J. Chem. Eng. Data, 1979, 24, 3, 175-178, https://doi.org/10.1021/je60082a012
. [all data]
Barbillon, Schuffenecker, et al., 1991
Barbillon, P.; Schuffenecker, L.; Dellacherie, J.; Balesdent, D.; Dirande, M.,
Variation d'enthalpie subie de 260 K a 340 K par les n-paraffines, comprises entrel'octadecane et l'hexacosane,
J. Chim. Phys. Phys.-Chim. Biol., 1991, 88, 91-113. [all data]
Kolesnikov and Syunyaev, 1985
Kolesnikov, S.I.; Syunyaev, Z.I.,
Phase transitions in the melting and crystallization of n-C18H38 and n-C20H42,
Zhur. Prikl. Khim. (Leningrad), 1985, 58(10), 2267-2271. [all data]
Company, 1973
Company, J.C.,
Measurement and interpretation of crystallization equilibriums of heavy paraffin and aromatic hydrocarbon solutions,
Chem. Eng. Sci., 1973, 28, 318-323. [all data]
Khimeche, Boumrah, et al., 2006
Khimeche, Kamel; Boumrah, Yacine; Benziane, Mokhtar; Dahmani, Abdallah,
Solid--liquid equilibria and purity determination for binary n-alkane+naphthalene systems,
Thermochimica Acta, 2006, 444, 2, 166-172, https://doi.org/10.1016/j.tca.2006.03.011
. [all data]
Genovese, Amarasinghe, et al., 2006
Genovese, A.; Amarasinghe, G.; Glewis, M.; Mainwaring, D.; Shanks, Robert A.,
Crystallisation, melting, recrystallisation and polymorphism of n-eicosane for application as a phase change material,
Thermochimica Acta, 2006, 443, 2, 235-244, https://doi.org/10.1016/j.tca.2006.02.008
. [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]
Syunyaev, Tumanyan, et al., 1984
Syunyaev, Z.I.; Tumanyan, B.P.; Kolesnikov, S.I.; Zhokhova, N.I.,
Some anomalies in melting points of binary mixtures of solid hydrocarbons,
Zhur. Prikl. Khim. (Leningrad), 1984, 57, 666-669. [all data]
Ksiazczak, 1989
Ksiazczak, A.,
Vapour pressures of binary three phase (solid+liquid+vapour) mixtures III. Melting temperatures of the solid phases of n-eicosane,
J. Chem. Thermodynam., 1989, 21, 789-792. [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, 2017-2019. [all data]
Claudy and Letoffe, 1991
Claudy, P.; Letoffe, J.M.,
Phase transitions in even n-alkanes CnH2n+2, n = 16-28. Characterization by differential calorimetric analysis and by thermooptical analysis. Effect of deuteration,
Calorim. Anal. Therm., 1991, 22, 281-290. [all data]
Rogers and Skanupong, 1974
Rogers, D.W.; Skanupong, S.,
Heats of hydrogenation of sixteen terminal monoolefins. The alternating effect,
J. Phys. Chem., 1974, 78, 2569-2572. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Cp,solid Constant pressure heat capacity of solid Pc Critical pressure S°solid,1 bar Entropy of solid at standard conditions (1 bar) Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Ttrs Temperature of phase transition ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔsubH Enthalpy of sublimation 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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