1,2-Butadiene Other names: Allene, methyl-; Buta-1,2-diene; CH2=C=CHCH3; Methylallene. InChI: InChI=1S/C4H6/c1-3-4-2/h4H,1H2,2H3 InChI Key: QNRMTGGDHLBXQZ-UHFFFAOYSA-N Formula: C4H6 SMILES: C=C=CC Molecular Weight: 54.09 CAS: 590-19-2 Physical Properties Property Value Unit Source PAff 778.90 kJ/mol NIST Webbook BasG 749.80 kJ/mol NIST Webbook ∆ H° -2593.80 ± 0.54 NIST Webbook c gas kJ/mol ∆ H° -2597.00 ± 1.20 NIST Webbook c gas kJ/mol ∆ G° 198.92 Joback Method f kJ/mol ∆ H° 162.20 ± 0.59 NIST Webbook f gas kJ/mol ∆ H° 165.40 ± 1.20 NIST Webbook f gas kJ/mol ∆ H° 6.97 Joback Method fus kJ/mol ∆ H° 23.68 NIST Webbook vap kJ/mol ∆ H° 23.90 NIST Webbook vap kJ/mol IE 9.03 eV NIST Webbook IE 9.23 ± 0.02 eV NIST Webbook IE 9.33 ± 0.02 eV NIST Webbook IE 9.00 eV NIST Webbook IE 9.33 eV NIST Webbook logP 1.35 Crippen Method oct/wat P 4640.32 Joback Method c kPa Property Value Unit Source S° 206.19 NIST Webbook liquid J/mol×K T 284.00 NIST Webbook boil K T 291.70 ± 2.00 NIST Webbook boil K T 284.06 ± 0.30 NIST Webbook boil K T 283.50 ± 0.50 NIST Webbook boil K T 467.79 Joback Method c K T 136.94 ± 0.05 NIST Webbook fus K T 136.96 ± 0.02 NIST Webbook fus K T 136.92 ± 0.06 NIST Webbook triple K T 136.95 ± 0.05 NIST Webbook triple K T 136.94 ± 0.08 NIST Webbook triple K V 0.22 3 Joback Method c m /kg-mol Temperature Dependent Properties Property Value Unit Temperature (K) Source C 81.17 J/mol×K 290.87 Joback Method p,gas C 122.80 290.0 NIST Webbook p,liquid J/mol×K ∆ H 6.95 136.9 NIST Webbook fus kJ/mol ∆ H 6.96 136.9 NIST Webbook fus kJ/mol ∆ H 6.96 136.92 NIST Webbook fus kJ/mol ∆ H 26.40 223.5 NIST Webbook vap kJ/mol ∆ H 25.20 237.5 NIST Webbook vap kJ/mol ∆ H 25.30 267.0 NIST Webbook vap kJ/mol ∆ H 24.60 ± 0.10 273.0 NIST Webbook vap kJ/mol ∆ H 24.62 273.24 NIST Webbook vap kJ/mol ∆ H 24.60 ± 0.30 273.25 NIST Webbook vap kJ/mol ∆ H 24.02 284.0 NIST Webbook vap kJ/mol Property Value Unit Temperature (K) Source ∆ S 50.84 136.92 NIST Webbook fus J/mol×K ∆ S 90.11 273.24 NIST Webbook vap J/mol×K Sources Joback Method: https://en.wikipedia.org/wiki/Joback_method NIST Webbook: http://webbook.nist.gov/cgi/inchi/InChI=1S/C4H6/c1-3-4-2/h4H,1H2,2H3 Crippen Method: http://pubs.acs.org/doi/abs/10.1021/ci990307l Legend PAff: Proton affinity (kJ/mol). BasG: Gas basicity (kJ/mol). ∆ H° : Standard gas enthalpy of combustion (kJ/mol). c gas C : Ideal gas heat capacity (J/mol×K). p,gas C : Liquid phase heat capacity (J/mol×K). p,liquid ∆ G°: Standard Gibbs free energy of formation (kJ/mol). f ∆ H° : Enthalpy of formation at standard conditions (kJ/mol). f gas ∆ H°: Enthalpy of fusion at standard conditions (kJ/mol). fus ∆ H: Enthalpy of fusion at a given temperature (kJ/mol). fus ∆ H°: Enthalpy of vaporization at standard conditions (kJ/mol). vap ∆ H: Enthalpy of vaporization at a given temperature (kJ/mol). vap IE: Ionization energy (eV). logP : Octanol/Water partition coefficient . oct/wat P : Critical Pressure (kPa). c ∆ S: Entropy of fusion at a given temperature (J/mol×K). fus S° : Liquid phase molar entropy at standard conditions (J/mol×K). liquid ∆ S: Entropy of vaporization at a given temperature (J/mol×K). vap T : Normal Boiling Point Temperature (K). boil T : Critical Temperature (K). c T : Normal melting (fusion) point (K). fus T : Triple Point Temperature (K). triple V : Critical Volume (m3/kg-mol). c Latest version available from: https://www.chemeo.com/cid/36-158-7/1%2C2-Butadiene Generated by Cheméo on Thu, 30 Sep 2021 11:07:52 +0000. Cheméo (https://www.chemeo.com) is the biggest free database of chemical and physical data for the process industry..