2-Butene, 2-methyl-
- Formula: C5H10
- Molecular weight: 70.1329
- IUPAC Standard InChIKey: BKOOMYPCSUNDGP-UHFFFAOYSA-N
- CAS Registry Number: 513-35-9
- 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: Trimethylethylene; β-Isoamylene; Amylene; 1,1,2-Trimethylethylene; 2-Methyl-2-butene; 3-Methyl-2-butene; (CH3)2C=CHCH3; 2-Methylbut-2-ene; n-Amylene; Ethylene, trimethyl-; UN 2460; 2-Methylbutene-2; NSC 74118; Isopentene
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Condensed phase thermochemistry 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:
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 | -68.6 ± 0.8 | kJ/mol | Eqk | Wiberg and Hao, 1991 | Heat of hydration; ALS |
ΔfH°liquid | -68.1 ± 1.3 | kJ/mol | Ccb | Good and Smith, 1979 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -3328.6 ± 1.3 | kJ/mol | Ccb | Good and Smith, 1979 | Corresponding ΔfHºliquid = -68.08 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 251.2 | J/mol*K | N/A | Chao, Hall, et al., 1983 | DH |
S°liquid | 251.04 | J/mol*K | N/A | Todd, Oliver, et al., 1947 | DH |
S°liquid | 248.9 | J/mol*K | N/A | Parks and Huffman, 1930 | Extrapolation below 90 K, 13.12 cal/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
152.8 | 298.15 | Chao, Hall, et al., 1983 | T = 13 to 301 K.; DH |
152.80 | 298.15 | Todd, Oliver, et al., 1947 | T = 12 to 300 K.; DH |
146.4 | 293.9 | Parks and Huffman, 1930 | T = 93 to 294 K. Value is unsmoothed experimental datum.; DH |
Phase change data
Go To: Top, Condensed phase 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:
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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 311. ± 1. | K | AVG | N/A | Average of 44 out of 45 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 140. ± 10. | K | AVG | N/A | Average of 10 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 139.40 | K | N/A | Chao, Hall, et al., 1983, 2 | Uncertainty assigned by TRC = 0.02 K; TRC |
Ttriple | 139.42 | K | N/A | Todd, Oliver, et al., 1947, 2 | Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 139.440 | K | N/A | Huffman, 1945 | Uncertainty assigned by TRC = 0.6 K; TRC |
Ttriple | 139.420 | K | N/A | Huffman, 1945 | Uncertainty assigned by TRC = 0.6 K; TRC |
Ttriple | 138.9 | K | N/A | Parks and Huffman, 1930, 2 | Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 470. ± 1. | K | N/A | Tsonopoulos and Ambrose, 1996 | |
Tc | 481. | K | N/A | Majer and Svoboda, 1985 | |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 34.2 ± 1.0 | bar | N/A | Tsonopoulos and Ambrose, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 27.34 | kJ/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 27.1 | kJ/mol | N/A | Reid, 1972 | AC |
ΔvapH° | 27.1 ± 0.1 | kJ/mol | C | Scott, Waddington, et al., 1949 | AC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
26.31 | 311.7 | N/A | Majer and Svoboda, 1985 | |
28.4 | 286. | A | Stephenson and Malanowski, 1987 | Based on data from 271. to 343. K.; AC |
28.3 | 291. | N/A | Scott, Waddington, et al., 1949 | Based on data from 276. to 344. K.; AC |
27.5 ± 0.1 | 290. | C | Scott, Waddington, et al., 1949 | AC |
26.3 ± 0.1 | 312. | C | Scott, Waddington, et al., 1949 | 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 |
---|---|---|---|---|---|
290. to 312. | 41.46 | 0.2688 | 481. | 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 | Comment |
---|---|---|---|---|---|
276.19 to 343.74 | 4.04727 | 1098.619 | -39.889 | Scott, Waddington, et al., 1949 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
7.579 | 139.40 | Chao, Hall, et al., 1983 | DH |
7.5973 | 139.42 | Todd, Oliver, et al., 1947 | DH |
7.59 | 139.4 | Domalski and Hearing, 1996 | AC |
7.435 | 138.9 | Parks and Huffman, 1930 | DH |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
54.37 | 139.40 | Chao, Hall, et al., 1983 | DH |
54.49 | 139.42 | Todd, Oliver, et al., 1947 | DH |
5.35 | 138.9 | Parks and Huffman, 1930 | DH |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Wiberg and Hao, 1991
Wiberg, K.B.; Hao, S.,
Enthalpies of hydration of alkenes. 4. Formation of acyclic tert-alcohols,
J. Org. Chem., 1991, 56, 5108-5110. [all data]
Good and Smith, 1979
Good, W.D.; Smith, N.K.,
The enthalpies of combustion of the isomeric pentenes in the liquid state. A warning to combustion calorimetrists about sample drying,
J. Chem. Thermodyn., 1979, 11, 111-118. [all data]
Chao, Hall, et al., 1983
Chao, J.; Hall, K.R.; Yao, J.M.,
Thermodynamic properties of simple alkenes,
Thermochim. Acta, 1983, 64(3), 285-303. [all data]
Todd, Oliver, et al., 1947
Todd, S.S.; Oliver, G.D.; Huffman, H.M.,
The heat capacities, heats of fusion and entropies of the six pentenes,
J. Am. Chem. Soc., 1947, 69, 1519-1525. [all data]
Parks and Huffman, 1930
Parks, G.S.; Huffman, H.M.,
Thermal data on organic compounds. IX. A study of the effect of unsaturation on the heat capacities, entropies and free energies of some hydrocarbons and other compounds,
J. Am. Chem. Soc., 1930, 52, 4381-4391. [all data]
Chao, Hall, et al., 1983, 2
Chao, J.; Hall, K.R.; Yao, J.M.,
Thermodynamic Properties of Simple Alkenes,
Thermochim. Acta, 1983, 64, 285. [all data]
Todd, Oliver, et al., 1947, 2
Todd, S.S.; Oliver, G.D.; Huffman, H.M.,
The heat capacities, heats of fusion and entropies of the six pentenes.,
J. Am. Chem. Soc., 1947, 69, 1519. [all data]
Huffman, 1945
Huffman, H.M.,
Personal Commun., U. S. Bur. Mines, Bartlesville, OK, July 25, 1945. [all data]
Parks and Huffman, 1930, 2
Parks, G.S.; Huffman, H.M.,
Thermal data on organic compounds. IX. A study of the effect of unsaturation on the heat capacities, entropies and free energies of some hydrocarbons and other compounds,
J. Am. Chem. Soc., 1930, 52, 4381. [all data]
Tsonopoulos and Ambrose, 1996
Tsonopoulos, C.; Ambrose, D.,
Vapor-Liquid Critical Properties of Elements and Compounds. 6. Unsaturated Aliphatic Hydrocarbons,
J. Chem. Eng. Data, 1996, 41, 645-656. [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]
Scott, Waddington, et al., 1949
Scott, D.W.; Waddington, G.; Smith, J.C.; Huffman, H.M.,
Thermodynamic properties of three isomeric pentenes,
J. Am. Chem. Soc., 1949, 71, 2767-2773. [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]
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]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
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 ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion 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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