Pentane, 2,3-dimethyl-
- Formula: C7H16
- Molecular weight: 100.2019
- IUPAC Standard InChIKey: WGECXQBGLLYSFP-UHFFFAOYSA-N
- CAS Registry Number: 565-59-3
- 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. - Stereoisomers:
- Other names: 2,3-Dimethylpentane; 3,4-Dimethylpentane
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Condensed phase thermochemistry data
Go To: Top, 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 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 | -233.5 ± 1.3 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
ΔfH°liquid | -233. ± 1. | kJ/mol | Ccb | Davies and Gilbert, 1941 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -4807.8 ± 1.2 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -233.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -4808. ± 1. | kJ/mol | Ccb | Davies and Gilbert, 1941 | Corresponding ΔfHºliquid = -233.6 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 297.1 | J/mol*K | N/A | Finke, Messerly, et al., 1976 | DH |
S°liquid | 306.3 | J/mol*K | N/A | Huffman, Parks, et al., 1930 | Extrapolation below 70 K, 69.5 J/mol*K. Forms glass at low temperatures. Value includes estimated zero point entropy of 17 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
218.3 | 298.15 | Finke, Messerly, et al., 1976 | T = 10 to 400 K.; DH |
215.9 | 291.5 | Huffman, Parks, et al., 1930 | T = 68 to 292 K. Value is unsmoothed experimental datum.; DH |
Phase change data
Go To: Top, Condensed phase thermochemistry 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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
BS - Robert L. Brown and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 362.9 ± 0.3 | K | AVG | N/A | Average of 35 out of 39 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 149.36 | K | N/A | Anonymous, 1961 | Uncertainty assigned by TRC = 0.05 K; TRC |
Tfus | 139.85 | K | N/A | Brooks, Cleaton, et al., 1937 | Uncertainty assigned by TRC = 1. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 537.3 ± 0.5 | K | N/A | Daubert, 1996 | |
Tc | 537.29 | K | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tc | 537. | K | N/A | Francis, 1957 | Uncertainty assigned by TRC = 1. K; TRC |
Tc | 537.75 | K | N/A | Edgar and Calingaert, 1929 | Uncertainty assigned by TRC = 0.5 K; measured by Keys and Kleinschmidt; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 29.1 ± 0.5 | bar | N/A | Daubert, 1996 | |
Pc | 29.080 | bar | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4053 bar; TRC |
Pc | 29.5869 | bar | N/A | Edgar and Calingaert, 1929 | Uncertainty assigned by TRC = 0.5066 bar; measured by Keys and Kleinschmidt; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.393 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.54 ± 0.05 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.54 | mol/l | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 34.3 ± 0.1 | kJ/mol | C | Majer, Svoboda, et al., 1979 | AC |
ΔvapH° | 34.2 ± 0.1 | kJ/mol | C | Osborne and Ginnings, 1947 | AC |
ΔvapH° | 34.23 | kJ/mol | C | Osborne and Ginnings, 1947, 2 | ALS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
33.0 | 324. | N/A | Montón, de la Torre, et al., 1999 | Based on data from 309. to 371. K.; AC |
35.9 | 271. | A | Stephenson and Malanowski, 1987 | Based on data from 208. to 286. K.; AC |
34.5 | 301. | A | Stephenson and Malanowski, 1987 | Based on data from 286. to 365. K. See also Kkykj and Repas, 1973.; AC |
33.4 ± 0.1 | 313. | C | Majer, Svoboda, et al., 1979 | AC |
32.2 ± 0.1 | 333. | C | Majer, Svoboda, et al., 1979 | AC |
31.1 ± 0.1 | 353. | C | Majer, Svoboda, et al., 1979 | AC |
34.4 | 306. | N/A | Forziati, Norris, et al., 1949 | Based on data from 291. to 364. K.; 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 |
---|---|---|---|---|---|
290.67 to 363.83 | 3.98682 | 1242.609 | -50.806 | Forziati, Norris, et al., 1949, 2 | Coefficents calculated by NIST from author's data. |
Mass spectrum (electron ionization)
Go To: Top, Condensed phase thermochemistry data, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Due to licensing restrictions, this spectrum cannot be downloaded.
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 | Chemical Concepts |
NIST MS number | 151337 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, 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.
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]
Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C.,
Heats of combustion and formation of the nine isomeric heptanes in the liquid state,
J. Am. Chem. Soc., 1941, 63, 2730-2732. [all data]
Finke, Messerly, et al., 1976
Finke, H.L.; Messerly, J.F.; Douslin, D.R.,
Low-temperature thermal quantities for five alkyl-substituted pentanes,
J. Chem. Thermodynam., 1976, 8, 965-983. [all data]
Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Thomas, S.B.,
Thermal data on organic compounds. VIII. The heat capacities, entropies and free energies of the isomeric heptanes,
J. Am. Chem. Soc., 1930, 52, 3241-3251. [all data]
Anonymous, 1961
Anonymous, R.,
Preliminary thermodyn. prop. of FREON-14, E. I. Du Pont, Freon Tech. Bull. T-14, 1961. [all data]
Brooks, Cleaton, et al., 1937
Brooks, D.B.; Cleaton, R.B.; Carter, F.R.,
Paraffin Hydrocarbons Isolated from Crude Synthetic Isooctane (2,2,4-Trimethylpentane),
J. Res. Natl. Bur. Stand. (U. S.), 1937, 19, 319. [all data]
Daubert, 1996
Daubert, T.E.,
Vapor-Liquid Critical Properties of Elements and Compounds. 5. Branched Alkanes and Cycloalkanes,
J. Chem. Eng. Data, 1996, 41, 365-372. [all data]
McMicking and Kay, 1965
McMicking, J.H.; Kay, W.B.,
Vapor Pressures and Saturated Liquid and Vapor Densities of The Isomeric Heptanes and Isomeric Octanes,
Proc., Am. Pet. Inst., Sect. 3, 1965, 45, 75-90. [all data]
Francis, 1957
Francis, A.W.,
Pressure-Temperature-Liquid Density Relations of Pure Hydrocarbons,
Ind. Eng. Chem., 1957, 49, 1779. [all data]
Edgar and Calingaert, 1929
Edgar, G.; Calingaert, G.,
Preparation and Properties of the Isomeric Heptanes II. Physical Prop. properties,
J. Am. Chem. Soc., 1929, 51, 1540. [all data]
Majer, Svoboda, et al., 1979
Majer, Vladimír; Svoboda, Václav; Hála, Slavoj; Pick, Jirí,
Temperature dependence of heats of vaporization of saturated hydrocarbons C5-C8; Experimental data and an estimation method,
Collect. Czech. Chem. Commun., 1979, 44, 3, 637-651, https://doi.org/10.1135/cccc19790637
. [all data]
Osborne and Ginnings, 1947
Osborne, Nathan S.; Ginnings, Defoe C.,
Measurements of heat of vaporization and heat capacity of a number of hydrocarbons,
J. RES. NATL. BUR. STAN., 1947, 39, 5, 453-17, https://doi.org/10.6028/jres.039.031
. [all data]
Osborne and Ginnings, 1947, 2
Osborne, N.S.; Ginnings, D.C.,
Measurements of heat of vaporization and heat capacity of a number of hydrocarbons,
J. Res. NBS, 1947, 39, 453-477. [all data]
Montón, de la Torre, et al., 1999
Montón, Juan B.; de la Torre, Javier; Burguet, M.C.; Muñoz, Rosa; Loras, Sonia,
Isobaric Vapor-Liquid Equilibrium in the Systems 2,3-Dimethylpentane + Methyl 1,1-Dimethylethyl Ether, + Diisopropyl Ether and + Methyl 1,1-Dimethylpropyl Ether,
J. Chem. Eng. Data, 1999, 44, 6, 1158-1162, https://doi.org/10.1021/je990110p
. [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]
Kkykj and Repas, 1973
Kkykj, J.; Repas, M.,
Petrochemia, 1973, 13, 179. [all data]
Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D.,
Vapor pressures and boiling points of sixty API-NBS hydrocarbons,
J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050
. [all data]
Forziati, Norris, et al., 1949, 2
Forziati, A.F.; Norris, W.R.; Rossini, F.D.,
Vapor Pressures and Boiling Points of Sixty API-NBS Hydrocarbons,
J. Res. Natl. Bur. Stand. (U.S.), 1949, 43, 6, 555-563, https://doi.org/10.6028/jres.043.050
. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Pc Critical pressure S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Vc Critical volume ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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