Pentane, 3-methyl-
- Formula: C6H14
- Molecular weight: 86.1754
- IUPAC Standard InChIKey: PFEOZHBOMNWTJB-UHFFFAOYSA-N
- CAS Registry Number: 96-14-0
- 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: 3-Methylpentane; (C2H5)2CHCH3; UN 1208; UN 2462
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Phase change data
Go To: Top, Gas phase ion energetics 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
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 | 336.4 ± 0.4 | K | AVG | N/A | Average of 53 out of 57 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 155.15 | K | N/A | Hoog, Smittenberg, et al., 1937 | Uncertainty assigned by TRC = 2. K; TRC |
Tfus | 155.15 | K | N/A | Bruun and Hicks-Brunn, 1930 | Uncertainty assigned by TRC = 1. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 110.25 | K | N/A | Finke and Messerly, 1973 | Uncertainty assigned by TRC = 0.006 K; by extrapolation of 1/f to 0; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 504. ± 4. | K | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 30.7 ± 0.6 | atm | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.368 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.72 ± 0.02 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.72 | mol/l | N/A | Genco, Teja, et al., 1980 | Uncertainty assigned by TRC = 0.06 mol/l; TRC |
ρc | 2.73 | mol/l | N/A | Kay, 1946 | Uncertainty assigned by TRC = 0.02 mol/l; by extrapolation of rectilinear diameter to Tc; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 7.24 ± 0.04 | kcal/mol | AVG | N/A | Average of 6 values; Individual data points |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
6.707 | 336.4 | N/A | Majer and Svoboda, 1985 | |
7.15 | 331. | N/A | Loras, Aucejo, et al., 1999 | Based on data from 316. to 361. K.; AC |
7.29 | 308. | A | Stephenson and Malanowski, 1987 | Based on data from 293. to 338. K.; AC |
7.05 ± 0.02 | 313. | C | Majer, Svoboda, et al., 1979 | AC |
6.76 ± 0.02 | 333. | C | Majer, Svoboda, et al., 1979 | AC |
6.45 ± 0.02 | 353. | C | Majer, Svoboda, et al., 1979 | AC |
7.170 ± 0.002 | 303.1 | C | Waddington, Smith, et al., 1949 | ALS |
7.17 ± 0.02 | 303. | C | Waddington, Smith, et al., 1949 | AC |
6.88 ± 0.02 | 324. | C | Waddington, Smith, et al., 1949 | AC |
6.72 ± 0.02 | 336. | C | Waddington, Smith, et al., 1949 | AC |
7.22 | 303. | MM | Willingham, Taylor, et al., 1945 | Based on data from 288. to 337. K.; AC |
Enthalpy of vaporization
ΔvapH = A exp(-αTr)
(1 − Tr)β
ΔvapH =
Enthalpy of vaporization (at saturation pressure)
(kcal/mol)
Tr = reduced temperature (T / Tc)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | 298. to 353. |
---|---|
A (kcal/mol) | 10.81 |
α | 0. |
β | 0.2703 |
Tc (K) | 504.4 |
Reference | Majer and Svoboda, 1985 |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference |
---|---|---|---|---|
288.44 to 337.23 | 3.96806 | 1152.368 | -46.021 | Williamham, Taylor, et al., 1945 |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.27 | 110.3 | Domalski and Hearing, 1996 | AC |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
1.2675 | 110.26 | crystaline, I | liquid | Finke and Messerly, 1973, 2 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
11.496 | 110.26 | crystaline, I | liquid | Finke and Messerly, 1973, 2 | DH |
Gas phase ion energetics 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 as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.04 | EST | Luo and Pacey, 1992 | LL |
9.82 | EQ | Lias, Ausloos, et al., 1976 | LLK |
10.08 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C4H8+ | 10.58 ± 0.015 | C2H6 | PI | Steiner, Giese, et al., 1961 | RDSH |
C4H9+ | 10.95 ± 0.07 | C2H5 | PI | Steiner, Giese, et al., 1961 | RDSH |
C5H10+ | 10.70 ± 0.055 | CH4 | PI | Steiner, Giese, et al., 1961 | RDSH |
C5H11+ | 10.86 ± 0.085 | CH3 | PI | Steiner, Giese, et al., 1961 | RDSH |
References
Go To: Top, Phase change data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Hoog, Smittenberg, et al., 1937
Hoog, H.; Smittenberg, J.; Visser, G.H.,
Composition of the Primary Polymerization Prod. of Propene and Butenes
in IIe Congr. Mondial Pet. 2, Sect. 2, Phys. Chim. Raffin- age, p 489, 1937. [all data]
Bruun and Hicks-Brunn, 1930
Bruun, J.H.; Hicks-Brunn, M.M.,
The Isolation of the Isomers of Hexane from Petroleum,
J. Res. Natl. Bur. Stand. (U. S.), 1930, 5, 933. [all data]
Finke and Messerly, 1973
Finke, H.L.; Messerly, J.F.,
3-Methylpentane and 3-Methylheptane: Low-temperature Thermo. Properties properties,
J. Chem. Thermodyn., 1973, 5, 247. [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]
Genco, Teja, et al., 1980
Genco, J.M.; Teja, A.S.; Kay, W.B.,
Study of the critical and azeotropic behavior of binary mixtures I critical states of perfluoromethylcyclohexane + isomeric hexane systems,
J. Chem. Eng. Data, 1980, 25, 350. [all data]
Kay, 1946
Kay, W.B.,
The Vapor Pressures and Saturated Liquid and Vapor Densities of the Isomeric Hexanes,
J. Am. Chem. Soc., 1946, 68, 1336. [all data]
Majer and Svoboda, 1985
Majer, V.; Svoboda, V.,
Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]
Loras, Aucejo, et al., 1999
Loras, Sonia; Aucejo, Antonio; Muñoz, Rosa,
Vapor--liquid equilibria in the systems 3-methylpentane+methyl 1,1-dimethylethyl ether and 3-methylpentane+methyl 1,1-dimethylpropyl ether at 101.3 kPa,
Fluid Phase Equilibria, 1999, 156, 1-2, 185-195, https://doi.org/10.1016/S0378-3812(99)00028-X
. [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]
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]
Waddington, Smith, et al., 1949
Waddington, G.; Smith, J.C.; Scott, D.W.; Huffman, H.M.,
Experimental vapor heat capacities and heats of vaporization of 2-methylpentane, 3-methylpentane and 2,3-dimethylbutane,
J. Am. Chem. Soc., 1949, 71, 3902-3906. [all data]
Willingham, Taylor, et al., 1945
Willingham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D.,
Vapor pressures and boiling points of some paraffin, alkylcyclopentane, alkylcyclohexane, and alkylbenzene hydrocarbons,
J. RES. NATL. BUR. STAN., 1945, 35, 3, 219-17, https://doi.org/10.6028/jres.035.009
. [all data]
Williamham, Taylor, et al., 1945
Williamham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D.,
Vapor Pressures and Boiling Points of Some Paraffin, Alkylcyclopentane, Alkylcyclohexane, and Alkylbenzene Hydrocarbons,
J. Res. Natl. Bur. Stand. (U.S.), 1945, 35, 3, 219-244, https://doi.org/10.6028/jres.035.009
. [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]
Finke and Messerly, 1973, 2
Finke, H.L.; Messerly, J.F.,
3-Methylpentane and 3-methylheptane: low-temperature thermodynamic properties,
J. Chem. Thermodynam., 1973, 5, 247-257. [all data]
Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D.,
Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes,
Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]
Lias, Ausloos, et al., 1976
Lias, S.G.; Ausloos, P.; Horvath, Z.,
Charge transfer reactions in alkane and cycloalkane systems. Estimated ionization potentials,
Int. J. Chem. Kinet., 1976, 8, 725. [all data]
Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J.,
Ionization potentials of some molecules,
J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]
Steiner, Giese, et al., 1961
Steiner, B.; Giese, C.F.; Inghram, M.G.,
Photoionization of alkanes. Dissociation of excited molecular ions,
J. Chem. Phys., 1961, 34, 189. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔfusH Enthalpy of fusion 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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