2-Propenoic acid, 2-methyl-

• Formula: C₄H₆O₂
• Molecular weight: 86.0892
• IUPAC Standard InChI: InChI=1S/C4H6O2/c1-3(2)4(5)6/h1H2,2H3,(H,5,6) Copy

  
• IUPAC Standard InChIKey: CERQOIWHTDAKMF-UHFFFAOYSA-N Copy
• CAS Registry Number: 79-41-4
• 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: Methacrylic acid; α-Methylacrylic acid; Methylacrylic acid; 2-Methyl-2-propenoic acid; 2-Methylacrylic acid; CH2=C(CH3)COOH; 2-Methylpropenoic acid; Methacrylic acid glacial; α-Methacrylic acid; Acrylic acid, 2-methyl-; Propionic acid, 2-methylene-; Kyselina methakrylova; NSC 7393
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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
DH - Eugene S. Domalski and Elizabeth D. Hearing
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change data, Gas Chromatography, References, Notes

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:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₅O₂^- +  =

By formula: C₄H₅O₂^- + H⁺ = C₄H₆O₂

Gas Chromatography

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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

Normal alkane RI, non-polar column, temperature ramp

View large format table.

References

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, Notes

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

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

D'Souza and Teja, 1987
D'Souza, R.; Teja, A.S., The prediction of the vapor pressures of carboxylic acids, Chem. Eng. Commun., 1987, 61, 13. [all data]

Van-chin-syan, Kochubei, et al., 1996
Van-chin-syan, Yu.Ya.; Kochubei, V.V.; Sergeev, V.V.; Raevskii, Yu.A.; Gerasimchuk, S.I.; Kotovich, Kh.Z., Thermodynamic properties of some acids and aldehydes of the acrylic series, Sov. J. Chem. Phys. (Engl. Transl.), 1996, 70, 1789-1794, In original 1932. [all data]

Van-Chin-Syan, Kochubei, et al., 1996
Van-Chin-Syan, Yu.Ya.; Kochubei, V.V.; Sergeev, V.V.; Raevskii, Yu.A.; Gerasimchuk, S.I.; Kotovich, Kh.Z., Thermodynamic properties of some acrylic-series acids and aldehydes, Zh. Fiz. Khim., 1996, 70, 11, 1932. [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]

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]

Karabaev, Abduzhaminov, et al., 1985
Karabaev, M.K.; Abduzhaminov, T.P.; Kenisarin, M.M.; Saidov, A.A., Thermodynamics of the crystal-liquid phase transition in acrylates and methacrylates, Izv. Akad. Nauk Uzb. SSR, Ser. Fiz.-Mat. Nauk, 1985, (5), 74-77. [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [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]

Holmes, Terlouw, et al., 1979
Holmes, J.L.; Terlouw, J.K.; Vijfhuizen, P.C.; A'Campo, C., Metastable ion studies XII-Molecular and fragment ion structures for isomeric C₄H₆O₂ acids, Org. Mass Spectrom., 1979, 14, 204. [all data]

Burgers, Holmes, et al., 1982
Burgers, P.C.; Holmes, J.L.; Lossing, F.P.; Mommers, A.A.; Povel, F.R.; Terlouw, J.K., Isomeric and tautomeric [C₄H₄O]⁺ ions. Their thermochemistry and collisionally induced fragmentation characteristics, Can. J. Chem., 1982, 60, 2246. [all data]

Graul, Schnute, et al., 1990
Graul, S.T.; Schnute, M.E.; Squires, R.R., Gas-Phase Acidities of Carboxylic Acids and Alcohols from Collision-Induced Dissociation of Dimer Cluster Ions, Int. J. Mass Spectrom. Ion Proc., 1990, 96, 2, 181, https://doi.org/10.1016/0168-1176(90)87028-F . [all data]

Meynier, Novelli, et al., 1999
Meynier, A.; Novelli, E.; Chissolinim, R.; Zanardi, E.; Gandemer, G., Volatile compounds of commercial Milano salami, Meat Sci., 1999, 51, 2, 175-183, https://doi.org/10.1016/S0309-1740(98)00122-3 . [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, References

• Symbols used in this document:
  

  AE	Appearance energy
  Pc	Critical pressure
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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