1,2-Butadiene, 3-methyl-
- Formula: C5H8
- Molecular weight: 68.1170
- IUPAC Standard InChIKey: PAKGDPSCXSUALC-UHFFFAOYSA-N
- CAS Registry Number: 598-25-4
- 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: 1,1-Dimethylallene; 1,1-Dimethylallylene; 2-Methyl-2,3-butadiene; 3-Methyl-1,2-butadiene; 3,3-Dimethylallene; CH2=C=C(CH3)2; 3-methylbuta-1,2-diene
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Gas phase thermochemistry data
Go To: Top, Condensed phase 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:
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 | 129.07 ± 0.57 | kJ/mol | Ccr | Steele, Chirico, et al., 1990 | ALS |
ΔfH°gas | 129.1 | kJ/mol | N/A | Good, 1969 | Value computed using ΔfHliquid° value of 101.2±0.5 kj/mol from Good, 1969 and ΔvapH° value of 27.9 kj/mol from missing citation.; DRB |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 321.21 | J/mol*K | N/A | Messerly J.F., 1970 | GT |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
38.20 | 50. | Thermodynamics Research Center, 1997 | GT |
55.62 | 100. | ||
69.75 | 150. | ||
82.12 | 200. | ||
99.38 | 273.15 | ||
105.25 | 298.15 | ||
105.68 | 300. | ||
128.46 | 400. | ||
149.03 | 500. | ||
166.94 | 600. | ||
182.47 | 700. | ||
196.0 | 800. | ||
207.7 | 900. | ||
217.9 | 1000. | ||
226.8 | 1100. | ||
234.5 | 1200. | ||
241.1 | 1300. | ||
246.8 | 1400. | ||
251.8 | 1500. |
Condensed phase thermochemistry data
Go To: Top, Gas phase 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:
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 | 101.2 ± 0.50 | kJ/mol | Ccb | Good, 1969 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -3212.1 ± 0.42 | kJ/mol | Ccb | Good, 1969 | Corresponding ΔfHºliquid = 101.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 231.79 | J/mol*K | N/A | Messerly, Todd, et al., 1970 | DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
152.42 | 298.15 | Messerly, Todd, et al., 1970 | T = 12 to 320 K.; DH |
151.1 | 298.15 | Good, 1969 | DH |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, 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 by: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
View reactions leading to C5H8+ (ion structure unspecified)
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.9 | EI | Harris, McKinnon, et al., 1979 | |
8.95 ± 0.02 | PE | Bieri, Burger, et al., 1977 | |
8.95 | PE | Brogli, Crandall, et al., 1973 | Vertical value |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase 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.
Steele, Chirico, et al., 1990
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Hossenlopp, I.A.; Smith, N.K.,
Determination of ideal-gas enthalpies of formation for key compounds,
Am. Inst. Chem. Eng. Symp. Ser. (AIChE Symp. Ser.), 1990, 138-154. [all data]
Good, 1969
Good, W.D.,
3-Methyl-1,2-butadiene: Enthalpies of combustion and formation,
J. Chem. Eng. Data, 1969, 14, 480-481. [all data]
Messerly J.F., 1970
Messerly J.F.,
Chemical thermodynamic properties of the pentadienes. Third law studies,
J. Chem. Eng. Data, 1970, 15, 227-232. [all data]
Thermodynamics Research Center, 1997
Thermodynamics Research Center,
Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]
Messerly, Todd, et al., 1970
Messerly, J.F.; Todd, S.S.; Guthrie, G.B.,
Chemical thermodynamic properties of the pentadienes,
J. Chem. Eng. Data, 1970, 15, 227-232. [all data]
Harris, McKinnon, et al., 1979
Harris, D.; McKinnon, S.; Boyd, R.K.,
The origins of the base peak in the electron impact spectrum of limonene,
Org. Mass Spectrom., 1979, 14, 265. [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]
Brogli, Crandall, et al., 1973
Brogli, F.; Crandall, J.K.; Heilbronner, E.; Kloster-Jensen, E.; Sojka, S.A.,
The photoelectron spectra of methyl-substituted allenes and of tetramethyl-bisallenyl,
J. Electron Spectrosc. Relat. Phenom., 1973, 2, 455. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid S°gas Entropy of gas at standard conditions S°liquid Entropy of liquid at standard conditions 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 - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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