Pentane, 2,3-dimethyl-

Formula: C₇H₁₆
Molecular weight: 100.2019
IUPAC Standard InChI: InChI=1S/C7H16/c1-5-7(4)6(2)3/h6-7H,5H2,1-4H3
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
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Stereoisomers:
- pentane, 2,3-dimethyl-, (R)-
- (S)-2,3-dimethylpentane
Other names: 2,3-Dimethylpentane; 3,4-Dimethylpentane
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Phase change data

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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
T_boil	362.9 ± 0.3	K	AVG	N/A	Average of 35 out of 39 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
T_fus	149.36	K	N/A	Anonymous, 1961	Uncertainty assigned by TRC = 0.05 K; TRC
T_fus	139.85	K	N/A	Brooks, Cleaton, et al., 1937	Uncertainty assigned by TRC = 1. K; TRC
Quantity	Value	Units	Method	Reference	Comment
T_c	537.3 ± 0.5	K	N/A	Daubert, 1996
T_c	537.29	K	N/A	McMicking and Kay, 1965	Uncertainty assigned by TRC = 0.4 K; TRC
T_c	537.	K	N/A	Francis, 1957	Uncertainty assigned by TRC = 1. K; TRC
T_c	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
P_c	29.1 ± 0.5	bar	N/A	Daubert, 1996
P_c	29.080	bar	N/A	McMicking and Kay, 1965	Uncertainty assigned by TRC = 0.4053 bar; TRC
P_c	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
V_c	0.393	l/mol	N/A	Daubert, 1996
Quantity	Value	Units	Method	Reference	Comment
ρ_c	2.54 ± 0.05	mol/l	N/A	Daubert, 1996
ρ_c	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
Δ_vapH°	34.3 ± 0.1	kJ/mol	C	Majer, Svoboda, et al., 1979	AC
Δ_vapH°	34.2 ± 0.1	kJ/mol	C	Osborne and Ginnings, 1947	AC
Δ_vapH°	34.23	kJ/mol	C	Osborne and Ginnings, 1947, 2	ALS

Enthalpy of vaporization

Δ_vapH (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.

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:

References

Go To: Top, Phase change data, Notes

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

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Symbols used in this document:

P_c	Critical pressure
T_boil	Boiling point
T_c	Critical temperature
T_fus	Fusion (melting) point
V_c	Critical volume
Δ_vapH	Enthalpy of vaporization
Δ_vapH°	Enthalpy of vaporization at standard conditions
ρ_c	Critical density

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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