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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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -177.8 ± 1.0 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
93.14 | 200. | Scott D.W., 1974 | Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946] (see also [ Waddington G., 1949]).; GT |
128.32 | 273.15 | ||
139.4 ± 0.7 | 298.15 | ||
140.21 | 300. | ||
181.71 | 400. | ||
218.36 | 500. | ||
250.20 | 600. | ||
277.40 | 700. | ||
301.67 | 800. | ||
322.59 | 900. | ||
340.58 | 1000. | ||
356.90 | 1100. | ||
370.70 | 1200. | ||
384.93 | 1300. | ||
393.30 | 1400. | ||
405.85 | 1500. |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
158.07 | 341.60 | Waddington G., 1949 | GT |
170.25 | 371.20 | ||
182.55 | 402.30 | ||
195.52 | 436.00 | ||
208.24 | 471.15 |
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 | -207.0 ± 1.0 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -4154.9 ± 0.92 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -206.9 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 278.85 | J/mol*K | N/A | Adachi, Suga, et al., 1971 | DH |
S°liquid | 277.52 | J/mol*K | N/A | Douslin and Huffman, 1946 | DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
189.02 | 298.15 | Ohnishi, Fujihara, et al., 1989 | DH |
189.04 | 298.15 | Benson and D'Arcy, 1986 | DH |
188.67 | 298.15 | Benson, D'Arcy, et al., 1984 | DH |
188.77 | 298.15 | Aicart, Kumaran, et al., 1983 | DH |
188.77 | 298.15 | Benson, D'Arcy, et al., 1983 | DH |
188.80 | 298.15 | Wilhelm, Faradjzadeh, et al., 1982 | DH |
189.70 | 298.15 | Adachi, Suga, et al., 1971 | T = 13 to 300 K.; DH |
188.74 | 298.15 | Douslin and Huffman, 1946 | T = 13 to 300 K.; DH |
184.35 | 298.1 | Stull, 1937 | T = 140 to 320 K.; 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:
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 | 31.5 ± 0.8 | bar | 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° | 29.33 | kJ/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 29.1 | kJ/mol | N/A | Reid, 1972 | AC |
ΔvapH° | 29.12 | kJ/mol | C | Osborne and Ginnings, 1947 | ALS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
27.38 | 331.1 | N/A | Majer and Svoboda, 1985 | |
29.24 ± 0.01 | 295.8 | C | Waddington, Smith, et al., 1949 | ALS |
29.2 ± 0.1 | 296. | C | Waddington, Smith, et al., 1949 | AC |
28.9 ± 0.1 | 303. | C | Waddington, Smith, et al., 1949 | AC |
28.3 ± 0.1 | 313. | C | Waddington, Smith, et al., 1949 | AC |
27.3 ± 0.1 | 331. | C | Waddington, Smith, et al., 1949 | AC |
29.6 | 302. | MM | Willingham, Taylor, et al., 1945 | Based on data from 287. to 332. K.; AC |
29.2 ± 0.1 | 293. | C | Lemons and Felsing, 1943 | AC |
28.2 ± 0.1 | 313. | C | Lemons and Felsing, 1943 | AC |
27.0 ± 0.1 | 333. | C | Lemons and Felsing, 1943 | AC |
26.1 ± 0.1 | 353. | C | Lemons and Felsing, 1943 | AC |
Enthalpy of vaporization
ΔvapH =
A exp(-βTr) (1 − Tr)β
ΔvapH =
Enthalpy of vaporization (at saturation pressure)
(kJ/mol)
Tr = reduced temperature (T / Tc)
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Temperature (K) | A (kJ/mol) | β | Tc (K) | Reference | Comment |
---|---|---|---|---|---|
296. to 333. | 42.52 | 0.2518 | 499.9 | Majer and Svoboda, 1985 |
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 |
---|---|---|---|---|
287.41 to 331.94 | 3.93473 | 1127.187 | -44.2 | Williamham, Taylor, et al., 1945 |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
0.79 | 145.2 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
47.22 | 136.1 | Domalski and Hearing, 1996 | CAL |
22.13 | 107. | ||
5.47 | 145.2 |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
2.370 | 107. | crystaline, III | crystaline, I | Adachi, Suga, et al., 1971 | c,III has residual entropy of 2.7 J/mol*K.; DH |
6.425 | 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 |
0.7937 | 145.04 | crystaline, I | liquid | Adachi, Suga, et al., 1971 | DH |
6.494 | 136.07 | crystaline, II | crystaline, I | Douslin and Huffman, 1946 | DH |
0.8008 | 145.19 | crystaline, I | liquid | Douslin and Huffman, 1946 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
22.15 | 107. | crystaline, III | crystaline, I | Adachi, Suga, et al., 1971 | c,III; DH |
47.24 | 136.02 | crystaline, II | crystaline, I | Adachi, Suga, et al., 1971 | c,II; DH |
5.47 | 145.04 | crystaline, I | liquid | Adachi, Suga, et al., 1971 | DH |
47.72 | 136.07 | crystaline, II | crystaline, I | Douslin and Huffman, 1946 | DH |
5.52 | 145.19 | crystaline, I | liquid | Douslin and Huffman, 1946 | DH |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, 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: 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: 2H2 + C6H10 = C6H14
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -231.4 ± 3.0 | kJ/mol | Chyd | Molnar, Rachford, et al., 1984 | liquid phase; solvent: Dioxane |
ΔrH° | -227.0 ± 2.8 | kJ/mol | Chyd | Molnar, Rachford, et al., 1984 | liquid phase; solvent: Hexane |
ΔrH° | -223.4 ± 0.63 | kJ/mol | Chyd | Dolliver, Gresham, et al., 1937 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -225.4 ± 0.63 kJ/mol; At 355 °K |
By formula: H2 + C6H12 = C6H14
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -108.7 ± 0.45 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
ΔrH° | -110.4 ± 0.42 | kJ/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1936 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -111.4 ± 0.42 kJ/mol; At 355 K |
By formula: H2 + C6H12 = C6H14
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -116.3 ± 0.58 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
ΔrH° | -116.1 ± 0.4 | kJ/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1936 | gas phase |
By formula: C6H14 = C6H14
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -8.20 ± 0.84 | kJ/mol | Ciso | Prosen and Rossini, 1941 | liquid phase; Calculated from ΔHc |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, 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]
Scott D.W., 1974
Scott D.W.,
Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]
Scott D.W., 1974, 2
Scott D.W.,
Correlation of the chemical thermodynamic properties of alkane hydrocarbons,
J. Chem. Phys., 1974, 60, 3144-3165. [all data]
Pitzer K.S., 1946
Pitzer K.S.,
The entropies and related properties of branched paraffin hydrocarbons,
Chem. Rev., 1946, 39, 435-447. [all data]
Waddington G., 1949
Waddington G.,
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]
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]
Ohnishi, Fujihara, et al., 1989
Ohnishi, K.; Fujihara, I.; Murakami, S.,
Thermodynamic properties of decalins mixed with hexane isomers at 298.15K. 1. Excess enthalpies and excess isobaric heat capacities,
Fluid Phase Equilib., 1989, 46, 59-72. [all data]
Benson and D'Arcy, 1986
Benson, G.C.; D'Arcy, P.J.,
Heat capacities of binary mixtures of n-octane with each of the hexane isomers at 298.15 K,
Can. J. Chem., 1986, 64, 2139-2141. [all data]
Benson, D'Arcy, et al., 1984
Benson, G.C.; D'Arcy, P.J.; Kumaran, M.K.,
Heat capacities of binary mixtures of n-heptane with hexane isomers,
Thermochim. Acta, 1984, 75, 353-360. [all data]
Aicart, Kumaran, et al., 1983
Aicart, E.; Kumaran, M.K.; Halpin, C.J.; Benson, G.C.,
Ultrasonic speeds and isentropic compressibilities of 2-methylpentan-1-ol with hexane isomers at 298.15 K,
J. Chem. Thermodynam., 1983, 15, 1189-1197. [all data]
Benson, D'Arcy, et al., 1983
Benson, G.C.; D'Arcy, P.J.; Sugamori, M.E.,
Heat capacities of binary mixtures of 1-hexanol with hexane isomers at 298.15 K,
Thermochim. Acta, 1983, 71, 161-166. [all data]
Wilhelm, Faradjzadeh, et al., 1982
Wilhelm, E.; Faradjzadeh, A.; Grolier, J.-P.E.,
Excess volumes and excess heat capacities of 2,3-dimethylbutane + butane and + toluene,
J. Chem. Thermodynam., 1982, 14, 1199-1200. [all data]
Stull, 1937
Stull, D.R.,
A semi-micro calorimeter for measuring heat capacities at low temperatures,
J. Am. Chem. Soc., 1937, 59, 2726-2733. [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]
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]
Molnar, Rachford, et al., 1984
Molnar, A.; Rachford, R.; Smith, G.V.; Liu, R.,
Heats of hydrogenation by a simple and rapid flow calorimetric method,
Appl. Catal., 1984, 9, 219-223. [all data]
Dolliver, Gresham, et al., 1937
Dolliver, M.a.; Gresham, T.L.; Kistiakowsky, G.B.; Vaughan, W.E.,
Heats of organic reactions. V. Heats of hydrogenation of various hydrocarbons,
J. Am. Chem. Soc., 1937, 59, 831-841. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Rogers, Crooks, et al., 1987
Rogers, D.W.; Crooks, E.; Dejroongruang, K.,
Enthalpies of hydrogenation of the hexenes,
J. Chem. Thermodyn., 1987, 19, 1209-1215. [all data]
Kistiakowsky, Ruhoff, et al., 1936
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E.,
Heats of organic reactions. III. Hydrogenation of some higher olefins,
J. Am. Chem. Soc., 1936, 58, 137-145. [all data]
Prosen and Rossini, 1941
Prosen, E.J.R.; Rossini, F.D.,
Heats of isomerization of the five hexanes,
J. Res. NBS, 1941, 27, 289-310. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas 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 Ttriple Triple point temperature Vc Critical volume 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 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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