2-Pentyne

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-3-5-4-2/h3H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: NKTDTMONXHODTI-UHFFFAOYSA-N Copy
• CAS Registry Number: 627-21-4
• 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: Ethylmethylacetylene; 1-Ethyl-2-methylacetylene; C2H5C≡CCH3; pent-2-yne
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • References
  • Notes
• Other data available:
  • Phase change data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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

Constant pressure heat capacity of gas

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

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₅H₈⁺ (ion structure unspecified)

Ionization energy determinations

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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Additional Data

References

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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]

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]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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