Butane, 2,3-dimethyl-
- Formula: C6H14
- Molecular weight: 86.1754
- IUPAC Standard InChIKey: ZFFMLCVRJBZUDZ-UHFFFAOYSA-N
- CAS Registry Number: 79-29-8
- 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: Biisopropyl; Diisopropyl; 2,3-Dimethylbutane; (CH3)2CHCH(CH3)2; UN 2457
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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:
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
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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 331.2 ± 0.2 | K | AVG | N/A | Average of 65 out of 73 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 143. ± 6. | K | AVG | N/A | Average of 28 out of 29 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 144. ± 6. | K | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 500.1 ± 0.5 | K | AVG | N/A | Average of 11 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 31.1 ± 0.8 | atm | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.361 | l/mol | N/A | Daubert, 1996 | |
Vc | 0.360 | l/mol | N/A | Genco, Teja, et al., 1980 | Uncertainty assigned by TRC = 0.001 l/mol; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.77 ± 0.02 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.80 | mol/l | N/A | Kay, 1946 | Uncertainty assigned by TRC = 0.02 mol/l; by extrapolation of rectilinear diameter to Tc; TRC |
ρc | 2.798 | mol/l | N/A | Young, 1910 | Uncertainty assigned by TRC = 0.06 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 7.010 | kcal/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 6.96 | kcal/mol | N/A | Reid, 1972 | AC |
ΔvapH° | 6.960 | kcal/mol | C | Osborne and Ginnings, 1947 | ALS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
6.544 | 331.1 | N/A | Majer and Svoboda, 1985 | |
6.988 ± 0.003 | 295.8 | C | Waddington, Smith, et al., 1949 | ALS |
6.98 ± 0.02 | 296. | C | Waddington, Smith, et al., 1949 | AC |
6.91 ± 0.02 | 303. | C | Waddington, Smith, et al., 1949 | AC |
6.76 ± 0.02 | 313. | C | Waddington, Smith, et al., 1949 | AC |
6.52 ± 0.02 | 331. | C | Waddington, Smith, et al., 1949 | AC |
7.07 | 302. | MM | Willingham, Taylor, et al., 1945 | Based on data from 287. to 332. K.; AC |
6.98 ± 0.02 | 293. | C | Lemons and Felsing, 1943 | AC |
6.74 ± 0.02 | 313. | C | Lemons and Felsing, 1943 | AC |
6.45 ± 0.02 | 333. | C | Lemons and Felsing, 1943 | AC |
6.24 ± 0.02 | 353. | C | Lemons and Felsing, 1943 | AC |
Enthalpy of vaporization
ΔvapH =
A exp(-βTr) (1 − Tr)β
ΔvapH =
Enthalpy of vaporization (at saturation pressure)
(kcal/mol)
Tr = reduced temperature (T / Tc)
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Temperature (K) | A (kcal/mol) | β | Tc (K) | Reference | Comment |
---|---|---|---|---|---|
296. to 333. | 10.16 | 0.2518 | 499.9 | Majer and Svoboda, 1985 |
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 |
---|---|---|---|---|
287.41 to 331.94 | 3.92902 | 1127.187 | -44.2 | Williamham, Taylor, et al., 1945 |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
0.19 | 145.2 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
11.29 | 136.1 | Domalski and Hearing, 1996 | CAL |
5.289 | 107. | ||
1.31 | 145.2 |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.5664 | 107. | crystaline, III | crystaline, I | Adachi, Suga, et al., 1971 | c,III has residual entropy of 2.7 J/mol*K.; DH |
1.536 | 136.02 | crystaline, II | crystaline, I | Adachi, Suga, et al., 1971 | c,II stable form to 10 K; apparently has no zero point entropy.; DH |
0.1897 | 145.04 | crystaline, I | liquid | Adachi, Suga, et al., 1971 | DH |
1.552 | 136.07 | crystaline, II | crystaline, I | Douslin and Huffman, 1946 | DH |
0.1914 | 145.19 | crystaline, I | liquid | Douslin and Huffman, 1946 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
5.294 | 107. | crystaline, III | crystaline, I | Adachi, Suga, et al., 1971 | c,III; DH |
11.29 | 136.02 | crystaline, II | crystaline, I | Adachi, Suga, et al., 1971 | c,II; DH |
1.31 | 145.04 | crystaline, I | liquid | Adachi, Suga, et al., 1971 | DH |
11.41 | 136.07 | crystaline, II | crystaline, I | Douslin and Huffman, 1946 | DH |
1.32 | 145.19 | crystaline, I | liquid | Douslin and Huffman, 1946 | 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 |
9.79 | EQ | Lias, Ausloos, et al., 1976 | LLK |
10.02 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H6+ | 10.70 ± 0.02 | C3H8 | PI | Steiner, Giese, et al., 1961 | RDSH |
C3H7+ | 11.40 ± 0.07 | C3H7 | PI | Steiner, Giese, et al., 1961 | RDSH |
C5H10+ | 10.54 ± 0.03 | CH4 | PI | Steiner, Giese, et al., 1961 | RDSH |
C5H11+ | 10.72 ± 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.
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]
Young, 1910
Young, S.,
The Internal Heat of Vaporization constants of thirty pure substances,
Sci. Proc. R. Dublin Soc., 1910, 12, 374. [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]
Reid, 1972
Reid, Robert C.,
Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00,
AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637
. [all data]
Osborne and Ginnings, 1947
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]
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]
Lemons and Felsing, 1943
Lemons, Joe Fred; Felsing, W.A.,
The Heats of Vaporization of Some Hexanes 1,
J. Am. Chem. Soc., 1943, 65, 1, 46-48, https://doi.org/10.1021/ja01241a015
. [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]
Adachi, Suga, et al., 1971
Adachi, K.; Suga, H.; Seki, S.,
Calorimetric study of the glassy state. VI. Phase changes in crystalline and glassy-crystalline 2,3-dimethylbutane,
Bull. Chem. Soc. Japan, 1971, 44, 78-89. [all data]
Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M.,
Low-temperature thermal data on the five isometric hexanes,
J. Am. Chem. Soc., 1946, 68, 1704-1708. [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 ΔfusS Entropy 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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