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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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -9.92 ± 0.21 | kcal/mol | Eqk | Wiberg and Hao, 1991 | Heat of hydration; ALS |
ΔfH°gas | -9.80 | kcal/mol | N/A | Good and Smith, 1979 | Value computed using ΔfHliquid° value of -68.1±1.3 kj/mol from Good and Smith, 1979 and ΔvapH° value of 27.1 kj/mol from Wiberg and Hao, 1991.; DRB |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
26.530 ± 0.079 | 319.04 | Scott D.W., 1949 | GT |
29.391 ± 0.088 | 362.37 | ||
32.010 ± 0.096 | 402.26 | ||
34.19 ± 0.10 | 436.18 | ||
36.34 ± 0.11 | 471.09 |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
25.100 | 298.15 | Scott D.W., 1949 | Recommended results of statistical thermodynamics calculation are in good agreement with experimental data.; GT |
25.220 | 300. | ||
31.931 | 400. | ||
38.069 | 500. | ||
43.420 | 600. | ||
48.040 | 700. | ||
52.051 | 800. | ||
55.521 | 900. | ||
58.549 | 1000. | ||
61.159 | 1100. | ||
63.449 | 1200. | ||
65.418 | 1300. | ||
67.139 | 1400. | ||
68.630 | 1500. |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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 | -16.4 ± 0.2 | kcal/mol | Eqk | Wiberg and Hao, 1991 | Heat of hydration; ALS |
ΔfH°liquid | -16.27 ± 0.31 | kcal/mol | Ccb | Good and Smith, 1979 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -795.56 ± 0.30 | kcal/mol | Ccb | Good and Smith, 1979 | Corresponding ΔfHºliquid = -16.27 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 60.04 | cal/mol*K | N/A | Chao, Hall, et al., 1983 | DH |
S°liquid | 60.000 | cal/mol*K | N/A | Todd, Oliver, et al., 1947 | DH |
S°liquid | 59.49 | cal/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 (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
36.52 | 298.15 | Chao, Hall, et al., 1983 | T = 13 to 301 K.; DH |
36.520 | 298.15 | Todd, Oliver, et al., 1947 | T = 12 to 300 K.; DH |
34.99 | 293.9 | Parks and Huffman, 1930 | T = 93 to 294 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
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 | 33.8 ± 0.99 | atm | N/A | Tsonopoulos and Ambrose, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 6.534 | kcal/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 6.48 | kcal/mol | N/A | Reid, 1972 | AC |
ΔvapH° | 6.48 ± 0.02 | kcal/mol | C | Scott, Waddington, et al., 1949 | AC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
6.288 | 311.7 | N/A | Majer and Svoboda, 1985 | |
6.79 | 286. | A | Stephenson and Malanowski, 1987 | Based on data from 271. to 343. K.; AC |
6.76 | 291. | N/A | Scott, Waddington, et al., 1949 | Based on data from 276. to 344. K.; AC |
6.57 ± 0.02 | 290. | C | Scott, Waddington, et al., 1949 | AC |
6.29 ± 0.02 | 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)
(kcal/mol)
Tr = reduced temperature (T / Tc)
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Temperature (K) | A (kcal/mol) | β | Tc (K) | Reference | Comment |
---|---|---|---|---|---|
290. to 312. | 9.909 | 0.2688 | 481. | 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 | Comment |
---|---|---|---|---|---|
276.19 to 343.74 | 4.04156 | 1098.619 | -39.889 | Scott, Waddington, et al., 1949 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.811 | 139.40 | Chao, Hall, et al., 1983 | DH |
1.8158 | 139.42 | Todd, Oliver, et al., 1947 | DH |
1.81 | 139.4 | Domalski and Hearing, 1996 | AC |
1.777 | 138.9 | Parks and Huffman, 1930 | DH |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
12.99 | 139.40 | Chao, Hall, et al., 1983 | DH |
13.02 | 139.42 | Todd, Oliver, et al., 1947 | DH |
1.28 | 138.9 | Parks and Huffman, 1930 | DH |
Henry's Law 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: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
k°H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference |
---|---|---|---|
0.0045 | V | N/A |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Ion clustering data, Mass spectrum (electron ionization), 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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias
Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C5H10+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 8.69 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 193.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 186.4 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.69 | PI | Traeger, 1986 | LBLHLM |
8.68 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
8.682 ± 0.003 | PE | Masclet, Grosjean, et al., 1973 | LLK |
8.70 | EI | Lossing, 1972 | LLK |
8.83 ± 0.11 | EI | Gross and Wilkins, 1971 | LLK |
8.72 | PE | Frost and Sandhu, 1971 | LLK |
8.85 ± 0.04 | EI | Bock and Seidl, 1968 | RDSH |
8.67 ± 0.02 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
8.68 | PI | Bralsford, Harris, et al., 1960 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H6+ | 11.70 ± 0.11 | C2H4 | EI | Gross and Wilkins, 1971 | LLK |
C4H7+ | 10.80 | CH3 | PI | Traeger, 1986 | LBLHLM |
C4H7+ | 10.84 | CH3 | EI | Brand and Baer, 1984 | LBLHLM |
C4H7+ | 10.84 | CH3 | EI | Lossing, 1972 | LLK |
C4H7+ | 11.33 ± 0.12 | CH3 | EI | Gross and Wilkins, 1971 | LLK |
Ion clustering data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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: Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: C3H9Si+ + C5H10 = (C3H9Si+ • C5H10)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 38.2 | kcal/mol | PHPMS | Li and Stone, 1989 | gas phase; condesation |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 48.0 | cal/mol*K | PHPMS | Li and Stone, 1989 | gas phase; condesation |
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW-1329 |
NIST MS number | 233774 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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]
Scott D.W., 1949
Scott D.W.,
Thermodynamic properties of three isomeric pentenes,
J. Am. Chem. Soc., 1949, 71, 2767-2773. [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]
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Traeger, 1986
Traeger, J.C.,
Heat of formation for the 1-methylallyl cation by photoionization mass spectrometry,
J. Phys. Chem., 1986, 90, 4114. [all data]
Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P.,
Valence ionization enrgies of hydrocarbons,
Helv. Chim. Acta, 1977, 60, 2213. [all data]
Masclet, Grosjean, et al., 1973
Masclet, P.; Grosjean, D.; Mouvier, G.,
Alkene ionization potentials. Part I. Quantitative determination of alkyl group structural effects,
J. Electron Spectrosc. Relat. Phenom., 1973, 2, 225. [all data]
Lossing, 1972
Lossing, F.P.,
Free radicals by mass spectrometry. XLV. Ionization potentials and heats of formation of C3H3, C3H5, and C4H7 radicals and ions,
Can. J. Chem., 1972, 50, 3973. [all data]
Gross and Wilkins, 1971
Gross, M.L.; Wilkins, C.L.,
Computer-assisted ion cyclotron resonance appearance potential measurements for C5H10 isomers,
Anal. Chem., 1971, 43, 1624. [all data]
Frost and Sandhu, 1971
Frost, D.C.; Sandhu, J.S.,
Ionization potentials of ethylene and some methyl-substituted ethylenes as determined by photoelectron spectroscopy,
Indian J. Chem., 1971, 9, 1105. [all data]
Bock and Seidl, 1968
Bock, H.; Seidl, H.,
d-Orbitaleffekte in siliziumsubstituierten π-Elektronensystemen. VI. Spektroskopische Untersuchungen an Alkyl- und Silylathylenen,
J. Organometal. Chem., 1968, 13, 87. [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]
Bralsford, Harris, et al., 1960
Bralsford, R.; Harris, P.V.; Price, W.C.,
The effect of fluorine on the electronic spectra and ionization potentials of molecules,
Proc. Roy. Soc. (London), 1960, A258, 459. [all data]
Brand and Baer, 1984
Brand, W.A.; Baer, T.,
Dissociation dynamics of energy-selected C5H10+ ions,
J. Am. Chem. Soc., 1984, 106, 3154. [all data]
Li and Stone, 1989
Li, X.; Stone, J.A.,
Determination of the beta silicon effect from a mass spectrometric study of the association of trimethylsilylium ion with alkenes,
J. Am. Chem. Soc., 1989, 111, 15, 5586, https://doi.org/10.1021/ja00197a013
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid IE (evaluated) Recommended ionization energy 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 d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K 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 ΔrS° Entropy of reaction 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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