Isoprene

• Formula: C₅H₈
• Molecular weight: 68.1170
• IUPAC Standard InChI: InChI=1S/C5H8/c1-4-5(2)3/h4H,1-2H2,3H3 Copy

  
• IUPAC Standard InChIKey: RRHGJUQNOFWUDK-UHFFFAOYSA-N Copy
• CAS Registry Number: 78-79-5
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: 1,3-Butadiene, 2-methyl-; β-Methylbivinyl; Isopentadiene; 2-Methyl-1,3-butadiene; 2-Methylbutadiene; CH2=C(CH3)CH=CH2; 2-Methylbuta-1,3-diene; 3-Methyl-1,3-butadiene; NSC 9237
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• Information on this page:
  • Gas phase thermochemistry data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
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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

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.

Fraser and Prosen, 1955
Fraser, F.M.; Prosen, E.J., Heats of combustion and isomerization of six pentadienes and spiropentane, J. Res. NBS, 1955, 54, 143-148. [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]

Compton D.A.C., 1977
Compton D.A.C., Conformations of conjugated hydrocarbons. Part 2. A spectroscopic and thermodynamic study of cis- and trans-penta-1,3-diene, J. Chem. Soc. Perkin Trans. 2, 1977, 1311-1315. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  S°gas	Entropy of gas at standard conditions
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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