Butane, 2,2,3,3-tetramethyl-
- Formula: C8H18
- Molecular weight: 114.2285
- IUPAC Standard InChIKey: OMMLUKLXGSRPHK-UHFFFAOYSA-N
- CAS Registry Number: 594-82-1
- 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: Ethane, hexamethyl-; Hexamethylethane; 2,2,3,3-Tetramethylbutane; (CH3)3CC(CH3)3; Tetramethylbutane
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, 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:
DRB - Donald R. Burgess, Jr.
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 | -54.06 | kcal/mol | N/A | Good, 1972 | Value computed using ΔfHsolid° value of -269.1±1.2 kj/mol from Good, 1972 and ΔsubH° value of 42.9 kj/mol from Prosen and Rossini, 1945.; DRB |
ΔfH°gas | -53.99 ± 0.46 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 93.05 ± 0.30 | cal/mol*K | N/A | Scott D.W., 1952 | GT |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
31.040 | 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 good agreement with experimental data available for alkanes. However, large uncertainties could be expected at high temperatures.; GT |
41.260 | 273.15 | ||
44.7 ± 0.1 | 298.15 | ||
45.000 | 300. | ||
58.320 | 400. | ||
70.210 | 500. | ||
80.600 | 600. | ||
89.699 | 700. | ||
97.801 | 800. | ||
104.90 | 900. | ||
111.20 | 1000. | ||
116.80 | 1100. | ||
121.80 | 1200. | ||
126.00 | 1300. | ||
130.00 | 1400. | ||
134.00 | 1500. |
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°solid | -64.32 ± 0.28 | kcal/mol | Ccb | Good, 1972 | ALS |
ΔfH°solid | -64.24 ± 0.46 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -1302.93 ± 0.26 | kcal/mol | Ccb | Good, 1972 | Corresponding ΔfHºsolid = -64.31 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°solid | -1303.03 ± 0.44 | kcal/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºsolid = -64.21 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°solid,1 bar | 65.430 | cal/mol*K | N/A | Scott, Douslin, et al., 1952 | DH |
S°solid,1 bar | 61.40 | cal/mol*K | N/A | Parks, Huffman, et al., 1930 | Extrapolation below 90 K, 64.68 J/mol*K.; DH |
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
57.271 | 301.60 | Scott, Douslin, et al., 1952 | T = 12 to 374 K. Value is unsmoothed experimental datum.; DH |
55.50 | 295.4 | Parks, Huffman, et al., 1930 | T = 89 to 295 K. Value is unsmoothed experimental datum.; 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DRB - Donald R. Burgess, Jr.
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 | 379.6 ± 0.5 | K | AVG | N/A | Average of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 374. ± 3. | K | AVG | N/A | Average of 20 out of 21 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 373.97 | K | N/A | Scott, Douslin, et al., 1952, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.07 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 10.26 | kcal/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 10.26 | kcal/mol | C | Osborne and Ginnings, 1947 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 10.365 ± 0.050 | kcal/mol | V | Scott, Douslin, et al., 1952 | ALS |
ΔsubH° | 10.4 ± 0.05 | kcal/mol | N/A | Scott, Douslin, et al., 1952 | Based on data from 273. to 338. K. See also Cox and Pilcher, 1970.; AC |
ΔsubH° | 10.3 ± 0.2 | kcal/mol | C | Osborne and Ginnings, 1947, 2 | AC |
ΔsubH° | 10.3 | kcal/mol | N/A | Prosen and Rossini, 1945 | DRB |
Reduced pressure boiling point
Tboil (K) | Pressure (atm) | Reference | Comment |
---|---|---|---|
379.7 | 1.01 | Aldrich Chemical Company Inc., 1990 | BS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
79.6 | 383. | A | Stephenson and Malanowski, 1987 | Based on data from 377. to 390. K.; AC |
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 | Comment |
---|---|---|---|---|---|
273. to 338. | 5.07764 | 1724.764 | -38.383 | Scott, Douslin, et al., 1952, 3 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
10.4 | 301. | N/A | Stephenson and Malanowski, 1987 | Based on data from 286. to 377. K.; AC |
13.4 | 263. to 279. | A,MG | Linder, 1930 | AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.80 | 373.9 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
3.133 | 152.5 | Domalski and Hearing, 1996 | CAL |
4.818 | 373.9 |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.4780 | 152.5 | crystaline, II | crystaline, I | Scott, Douslin, et al., 1952 | DH |
1.802 | 373.9 | crystaline, I | liquid | Scott, Douslin, et al., 1952 | DH |
0.4799 | 148.1 | crystaline, II | crystaline, I | Parks, Huffman, et al., 1930 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
3.133 | 152.5 | crystaline, II | crystaline, I | Scott, Douslin, et al., 1952 | DH |
4.821 | 373.9 | crystaline, I | liquid | Scott, Douslin, et al., 1952 | DH |
3.241 | 148.1 | crystaline, II | crystaline, I | Parks, Huffman, et al., 1930 | DH |
Reaction 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 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: C8H18 = C8H18
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -4.50 ± 0.38 | kcal/mol | Ciso | Prosen and Rossini, 1945, 2 | liquid phase; Calculated from ΔHc |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, 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 evaluated as indicated in comments:
L - Sharon G. Lias
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.8 | eV | N/A | N/A | L |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.79 | EST | Luo and Pacey, 1992 | LL |
9.8 | PE | Szepes, Koranyi, et al., 1981 | LLK |
10.37 | PE | Kimura, Katsumata, et al., 1981 | LLK |
10.2 ± 0.05 | PE | Szepes, Koranyi, et al., 1981 | Vertical value; LLK |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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.
Good, 1972
Good, W.D.,
The enthalpies of combustion and formation of n-octane and 2,2,3,3-tetramethylbutane,
J. Chem. Thermodyn., 1972, 4, 709-714. [all data]
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., 1952
Scott D.W.,
2,2,3,3-Tetramethylbutane: heat capacity, heats of transition, fusion and sublimation, vapor pressure, entropy and thermodynamic functions,
J. Am. Chem. Soc., 1952, 74, 883-887. [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]
Scott, Douslin, et al., 1952
Scott, D.W.; Douslin, D.R.; Gross, M.E.; Oliver, G.D.; Huffman, H.M.,
2,2,3,3-Tetramethylbutane: Heat capacity, heats of transition, fusion and sublimation, vapor pressure, entropy and thermodynamic functions,
J. Am. Chem. Soc., 1952, 74, 883-887. [all data]
Parks, Huffman, et al., 1930
Parks, G.S.; Huffman, H.M.; Thomas, S.B.,
Thermal data on organic compounds. VI. The heat capacities, entropies and free energies of some saturated, non-benzenoid hydrocarbons,
J. Am. Chem. Soc., 1930, 52, 1032-1041. [all data]
Scott, Douslin, et al., 1952, 2
Scott, D.W.; Douslin, D.R.; Gross, M.E.; Oliver, G.D.; Huffman, H.M.,
2,2,3,3-Tetramethylbutane: Heat Caqpacity, Heats of Transition, Fusion and Sublimation, Vapor Pressure, Entropy and Thermodynamic Functions,
J. Am. Chem. Soc., 1952, 74, 883. [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]
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]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press Inc., London, 1970, 643. [all data]
Osborne and Ginnings, 1947, 2
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]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [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]
Scott, Douslin, et al., 1952, 3
Scott, D.W.; Douslin, D.R.; Gross, M.E.; Oliver, G.D.; Huffman, H.M.,
2,2,3,3-Tetramethylbutane: Heat Capacity, Heats of Transition, Fusion and Sublimation, Vapor Pressure, Entropy and Thermodynamic Functions,
J. Am. Chem. Soc., 1952, 74, 4, 883-886, https://doi.org/10.1021/ja01124a007
. [all data]
Linder, 1930
Linder, E.G.,
Vapor Pressures of Some Hydrocarbons,
J. Phys. Chem., 1930, 35, 2, 531-535, https://doi.org/10.1021/j150320a010
. [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]
Prosen and Rossini, 1945, 2
Prosen, E.J.; Rossini, F.D.,
Heats of isomerization of the 18 octanes,
J. Res. NBS, 1945, 34, 163-174. [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]
Szepes, Koranyi, et al., 1981
Szepes, L.; Koranyi, T.; Naray-Szabo, G.; Modelli, A.; Distefano, G.,
Ultraviolet photoelectron spectra of group IV hexamethyl derivatives containing a metal-metal bond,
J. Organomet. Chem., 1981, 217, 35. [all data]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Cp,solid Constant pressure heat capacity of solid IE (evaluated) Recommended ionization energy S°gas Entropy of gas at standard conditions S°solid,1 bar Entropy of solid at standard conditions (1 bar) Tboil Boiling point Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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