2-Butyne

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Gas 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas145.1 ± 1.0kJ/molCmProsen, Maron, et al., 1951ALS
Δfgas148.0 ± 1.5kJ/molCcbWagman, Kilpatrick, et al., 1945Unpublished work of E. J. Prosen; ALS
Quantity Value Units Method Reference Comment
Δcgas-2576.7 ± 0.96kJ/molCmProsen, Maron, et al., 1951Corresponding Δfgas = 145.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
39.1850.Thermodynamics Research Center, 1997p=1 bar. Selected values are in close agreement with other statistically calculated values [ Wagman D.D., 1945].; GT
48.43100.
56.69150.
63.57200.
74.10273.15
78.02298.15
78.32300.
94.73400.
110.38500.
124.30600.
136.49700.
147.14800.
156.45900.
164.551000.
171.591100.
177.711200.
183.01300.
187.61400.
191.71500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
84.56336.07Kistiakowsky G.B., 1940GT
89.66369.46

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 by: Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
liquid195.10J/mol*KN/AYost, Osborne, et al., 1941Extrapolated from 291.0 K. Anomalous heat capacity between 145 and 160 K. S obtained from total energy divided by average temperature.

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
124.14290.Yost, Osborne, et al., 1941T = 15 to 290 K.

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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Tboil300. ± 1.KAVGN/AAverage of 23 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus240.82KN/APomerantz, Fookson, et al., 1954Uncertainty assigned by TRC = 0.2 K; TRC
Tfus240.9KN/ABoord, Greenlee, et al., 1946Uncertainty assigned by TRC = 0.2 K; TRC
Tfus240.63KN/ABoord, Greenlee, et al., 1946Uncertainty assigned by TRC = 0.3 K; TRC
Tfus240.83KN/AHenne and Greenlee, 1945Uncertainty assigned by TRC = 0.1 K; TRC
Tfus240.5KN/AHeisig and Davis, 1935Uncertainty assigned by TRC = 0.3 K; TRC
Quantity Value Units Method Reference Comment
Ttriple240.8KN/AYost, Osborne, et al., 1941, 2Uncertainty assigned by TRC = 0.15 K; TRC
Ttriple240.93KN/AYost, Osborne, et al., 1941, 2Uncertainty assigned by TRC = 0.06 K; TRC
Quantity Value Units Method Reference Comment
Δvap26.7kJ/molN/AReid, 1972AC

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
26.945291.0N/AYost, Osborne, et al., 1941P = 71.46 kPa; DH
26.945291.00N/AOsborne, Garner, et al., 1940DH
29.255.AStephenson and Malanowski, 1987Based on data from 240. to 308. K.; AC
26.9 ± 0.3291.00CYost, Osborne, et al., 1941, 3ALS
26.9 ± 0.1291.CYost, Osborne, et al., 1941AC

Entropy of vaporization

ΔvapS (J/mol*K) Temperature (K) Reference Comment
92.59291.0Yost, Osborne, et al., 1941P; DH
92.59291.00Osborne, Garner, et al., 1940DH

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
37.4220.AStull, 1947Based on data from 200. to 239. K.; AC

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
9.2349240.92Yost, Osborne, et al., 1941DH
9.2328240.93Osborne, Garner, et al., 1940DH
9.25240.9Acree, 1991AC

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
38.348240.92Yost, Osborne, et al., 1941DH
38.33240.93Osborne, Garner, et al., 1940DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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 as indicated in comments:
B - John E. Bartmess
ALS - 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

C4H5- + Hydrogen cation = 2-Butyne

By formula: C4H5- + H+ = C4H6

Quantity Value Units Method Reference Comment
Δr1628. ± 8.8kJ/molG+TSGal, Decouzon, et al., 2001gas phase; Acid: MeC≡CMe; B
Δr1628. ± 14.kJ/molG+TSN/Agas phase; Measured vs pyridine; B
Quantity Value Units Method Reference Comment
Δr1597. ± 8.4kJ/molIMREGal, Decouzon, et al., 2001gas phase; Acid: MeC≡CMe; B
Δr1596. ± 13.kJ/molIMREN/Agas phase; Measured vs pyridine; B

2Hydrogen + 2-Butyne = Butane

By formula: 2H2 + C4H6 = C4H10

Quantity Value Units Method Reference Comment
Δr-272.4 ± 1.3kJ/molChydConn, Kistiakowsky, et al., 1939gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -274.4 ± 0.54 kJ/mol; At 355 K; ALS

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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 C4H6+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)9.58 ± 0.02eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)775.8kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity745.1kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.59 ± 0.02PEBieri, Burger, et al., 1977LLK
9.562 ± 0.005PECarlier, Dubois, et al., 1975LLK
9.61PEEnsslin, Bock, et al., 1974LLK
9.59PEBrogli, Heilbronner, et al., 1973LLK
9.56EILossing, 1972LLK
9.79PEBieri and Asbrink, 1980Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH3+17.6 ± 0.5?EICoats and Anderson, 1957RDSH
C2H3+14.7 ± 0.2?EICoats and Anderson, 1957RDSH
C3H3+11.04CH3EILossing, 1972LLK
C4H2+16.7 ± 0.3?EICoats and Anderson, 1957RDSH
C4H3+15.1 ± 0.2H2+HEICoats and Anderson, 1957RDSH
C4H4+14.0 ± 0.1H2EICoats and Anderson, 1957RDSH
C4H5+12.1 ± 0.1HEICoats and Anderson, 1957RDSH

De-protonation reactions

C4H5- + Hydrogen cation = 2-Butyne

By formula: C4H5- + H+ = C4H6

Quantity Value Units Method Reference Comment
Δr1628. ± 8.8kJ/molG+TSGal, Decouzon, et al., 2001gas phase; Acid: MeC≡CMe; B
Δr1628. ± 14.kJ/molG+TSN/Agas phase; Measured vs pyridine; B
Quantity Value Units Method Reference Comment
Δr1597. ± 8.4kJ/molIMREGal, Decouzon, et al., 2001gas phase; Acid: MeC≡CMe; B
Δr1596. ± 13.kJ/molIMREN/Agas phase; Measured vs pyridine; B

IR Spectrum

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Gas Phase Spectrum

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IR spectrum
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Additional Data

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Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center
State gas
Instrument HP-GC/MS/IRD

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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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Mass spectrum
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Additional Data

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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-IW- 744
NIST MS number 227606

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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.

Prosen, Maron, et al., 1951
Prosen, E.J.; Maron, F.W.; Rossini, F.D., Heats of combustion, formation, and insomerization of ten C4 hydrocarbons, J. Res. NBS, 1951, 46, 106-112. [all data]

Wagman, Kilpatrick, et al., 1945
Wagman, D.D.; Kilpatrick, J.E.; Pitzer, K.S.; Rossini, F.D., Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes, to 1,500° K, J. Res. NBS, 1945, 35, 467-496. [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]

Wagman D.D., 1945
Wagman D.D., Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes to 1500 K, J. Res. Nat. Bur. Stand., 1945, 35, 467-496. [all data]

Kistiakowsky G.B., 1940
Kistiakowsky G.B., Gaseous heat capacities. III, J. Chem. Phys., 1940, 8, 618-622. [all data]

Yost, Osborne, et al., 1941
Yost, D.M.; Osborne, D.W.; Garner, C.S., The heat capacity, entropy, and heats of transition, fusion, and vaporization of dimethylacetylene. Free rotation in the dimethylacetylene molecule, J. Am. Chem. Soc., 1941, 63, 3492-3496. [all data]

Pomerantz, Fookson, et al., 1954
Pomerantz, P.; Fookson, A.; Mears, T.W.; Rothberg, S.; Howard, F.L., Synthesis and Physical Properties of Several Acetylenic Hydrocarbons, J. Res. Natl. Bur. Stand. (U. S.), 1954, 52, 51. [all data]

Boord, Greenlee, et al., 1946
Boord, C.E.; Greenlee, K.W.; Perilstein, W.L., The Synthesis, Purification and Prop. of Hydrocarbons of Low Mol. Weight, Am. Pet. Inst. Res. Proj. 45, Eighth Annu. Rep., Ohio State Univ., June 30, 1946. [all data]

Henne and Greenlee, 1945
Henne, A.L.; Greenlee, K.W., Preparation and Physical Constants of Acetylenic Compounds, J. Am. Chem. Soc., 1945, 67, 484-5. [all data]

Heisig and Davis, 1935
Heisig, G.B.; Davis, H.M., Physical Constants of Dimethylacetylene, J. Am. Chem. Soc., 1935, 57, 339-40. [all data]

Yost, Osborne, et al., 1941, 2
Yost, D.M.; Osborne, D.W.; Garner, C.S., The Heat Capacity, Entropy, and Heats of Transition, Fusion, and Vaporization of Dimethylacetylene. Free Rotation in the Dimethylacetylene Molecule, J. Am. Chem. Soc., 1941, 63, 3492. [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, Garner, et al., 1940
Osborne, D.W.; Garner, C.S.; Yost, D.M., The entropy of dimethylacetylene from low temperature calorimetric measurements. Free rotation in the dimethylacetylene molecule, J. Chem. Phys., 1940, 8, 131. [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]

Yost, Osborne, et al., 1941, 3
Yost, D.M.; Osborne, D.W.; Garner, C.S., The heat capacity, entropy, and heats of transition, fusion, and vaporization of dimethylacetylene. Free rotation in the dimethylacetylene molecule, J. Am. Chem. Soc., 1941, 63, 3492-34. [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Acree, 1991
Acree, William E., Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation, Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H . [all data]

Gal, Decouzon, et al., 2001
Gal, J.F.; Decouzon, M.; Maria, P.C.; Gonzalez, A.I.; Mo, O.; Yanez, M.; El Chaouch, S.; Guillemin, J.C., Acidity trends in alpha,beta-unsaturated alkanes, silanes, germanes, and stannanes, J. Am. Chem. Soc., 2001, 123, 26, 6353-6359, https://doi.org/10.1021/ja004079j . [all data]

Conn, Kistiakowsky, et al., 1939
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A., Heats of organic reactions. VIII. Some further hydrogenations, including those of some acetylenes, J. Am. Chem. Soc., 1939, 61, 1868-1876. [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]

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]

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]

Carlier, Dubois, et al., 1975
Carlier, P.; Dubois, J.E.; Masclet, P.; Mouvier, G., Spectres de photoelectrons des alcynes, J. Electron Spectrosc. Relat. Phenom., 1975, 7, 55. [all data]

Ensslin, Bock, et al., 1974
Ensslin, W.; Bock, H.; Becker, G., Photoelectron spectra and molecular properties. XXX. π interactions in H3Si- H3C-substituted acetylenes, J. Am. Chem. Soc., 1974, 96, 2757. [all data]

Brogli, Heilbronner, et al., 1973
Brogli, F.; Heilbronner, E.; Hornung, V.; Kloster-Jensen, E., 230. Die photoelektronen-spektren methyl-substituierter Acetylene, Helv. Chim. Acta, 1973, 56, 2171. [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]

Bieri and Asbrink, 1980
Bieri, G.; Asbrink, L., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1980, 20, 149. [all data]

Coats and Anderson, 1957
Coats, F.H.; Anderson, R.C., Thermodynamic data from electron-impact measurements on acetylene and substituted acetylenes, J. Am. Chem. Soc., 1957, 79, 1340. [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, IR Spectrum, Mass spectrum (electron ionization), References