Isoprene
- Formula: C5H8
- Molecular weight: 68.1170
- IUPAC Standard InChI: InChI=1S/C5H8/c1-4-5(2)3/h4H,1-2H2,3H3
- IUPAC Standard InChIKey: RRHGJUQNOFWUDK-UHFFFAOYSA-N
- 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
View 3d structure (requires JavaScript / HTML 5) - 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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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 |
|---|---|---|---|---|---|
| ΔfH°gas | 75.7 ± 1.0 | kJ/mol | Cm | Fraser and Prosen, 1955 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°gas | -3186.6 ± 0.96 | kJ/mol | Cm | Fraser and Prosen, 1955 | Corresponding ΔfHºgas = 75.73 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas | 314.76 | 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 |
|---|---|---|---|
| 36.28 | 50. | Thermodynamics Research Center, 1997 | Values of S(T) and Cp(T) from other statistical mechanics calculation [ Compton D.A.C., 1977] are in close agreement with recommended ones.; GT |
| 47.75 | 100. | ||
| 60.95 | 150. | ||
| 74.81 | 200. | ||
| 95.64 | 273.15 | ||
| 102.69 | 298.15 | ||
| 103.21 | 300. | ||
| 129.59 | 400. | ||
| 152.16 | 500. | ||
| 171.03 | 600. | ||
| 186.95 | 700. | ||
| 200.6 | 800. | ||
| 212.3 | 900. | ||
| 222.5 | 1000. | ||
| 231.3 | 1100. | ||
| 238.9 | 1200. | ||
| 245.5 | 1300. | ||
| 251.2 | 1400. | ||
| 256.2 | 1500. |
Ion clustering 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: Robert C. Dunbar
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: Ag+ + C5H8 = (Ag+ • C5H8)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 164. ± 19. | kJ/mol | RAK | Ho, Yang, et al., 1997 |
References
Go To: Top, Gas phase thermochemistry data, Ion clustering data, Notes
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]
Ho, Yang, et al., 1997
Ho, Y.-P.; Yang, Y.-C.; Klippenstein, S.J.; Dunbar, R.C.,
Binding Energies of Ag+ and Cd+ Complexes from Analysis of Radiative Association Kinetics,
J. Phys. Chem. A, 1997, 101, 18, 3338, https://doi.org/10.1021/jp9637284
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Ion clustering 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 ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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