Propanoic acid, 2-methyl-

• Formula: C₄H₈O₂
• Molecular weight: 88.1051
• IUPAC Standard InChI: InChI=1S/C4H8O2/c1-3(2)4(5)6/h3H,1-2H3,(H,5,6) Copy

  
• IUPAC Standard InChIKey: KQNPFQTWMSNSAP-UHFFFAOYSA-N Copy
• CAS Registry Number: 79-31-2
• 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: Isobutyric acid; α-Methylpropanoic acid; α-Methylpropionic acid; Dimethylacetic acid; Isobutanoic acid; Isopropylformic acid; 2-Methylpropanoic acid; 2-Methylpropionic acid; iso-C3H7COOH; Acetic acid, dimethyl-; Cenex RP b2; Propionic acid, 2-methyl-; Tenox IBP 2; Kyselina isomaselna; UN 2529; Methylpropanoic acid; Methylpropionic acid; 2-Propanecarboxylic acid; i-Butyric acid; NSC 62780
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Condensed phase thermochemistry data

Go To: Top, Reaction thermochemistry data, Henry's Law data, References, Notes

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

Data compiled by: Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Reaction thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Henry's Law data, References, Notes

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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

 +  = ( • )

By formula: I^- + C₄H₈O₂ = (I^- • C₄H₈O₂)

 +  = ( • )

By formula: C₄H₇O₂^- + C₄H₈O₂ = (C₄H₇O₂^- • C₄H₈O₂)

 +  =

By formula: C₄H₇O₂^- + H⁺ = C₄H₈O₂

 +  =

By formula: H₂ + C₄H₆O₂ = C₄H₈O₂

 +  = 2

By formula: H₂O + C₈H₁₄O₃ = 2C₄H₈O₂

 +  =  + 

By formula: C₅H₁₀O₂ + H₂O = CH₄O + C₄H₈O₂

Henry's Law data

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, References, Notes

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

Data compiled by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

References

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Notes

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

Biros, Sikora, et al., 1982
Biros, J.; Sikora, A.; Zivny, A.; Pouchly, J., Heat capacity of monomer models of some hydrophilic polymers in aqueous solution from 20° to 60°C, Collect Czech. Chem. Commun., 1982, 47(10), 2692-2701. [all data]

Konicek and Wadso, 1971
Konicek, J.; Wadso, I., Thermochemical properties of some carboxylic acids, amines and N-substituted amides in aqueous solution, Acta Chem. Scand., 1971, 25, 1541-1551. [all data]

von Reis, 1881
von Reis, M.A., Die specifische Wärme flüssiger organischer Verbindungen und ihre Beziehung zu deren Moleculargewicht, Ann. Physik [3], 1881, 13, 447-464. [all data]

Caldwell and Kebarle, 1984
Caldwell, G.; Kebarle, P., Binding energies and structural effects in halide anion-ROH and -RCOOH complexes from gas phase equilibria measurements, J. Am. Chem. Soc., 1984, 106, 967. [all data]

Meot-Ner and Sieck, 1986
Meot-Ner, M.; Sieck, L.W., The ionic hydrogen bond and ion solvation. 5. OH...O^- bonds. Gas phase solvation and clustering of alkoxide and carboxylate anions, J. Am. Chem. Soc., 1986, 108, 7525. [all data]

Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P., Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria, Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092 . [all data]

Skinner and Snelson, 1959
Skinner, H.A.; Snelson, A., Heats of hydrogenation Part 3., Trans. Faraday Soc., 1959, 55, 405-407. [all data]

Conn, Kistiakowsky, et al., 1942
Conn, J.B.; Kistiakowsky, G.B.; Roberts, R.M.; Smith, E.A., Heats of organic reactions. XIII. Heats of hydrolysis of some acid anhydrides, J. Am. Chem. Soc., 1942, 64, 1747-17. [all data]

Guthrie and Cullimore, 1980
Guthrie, J.P.; Cullimore, P.A., Effect of the acyl substituent on the equilibrium constant for hydration of esters, Can. J. Chem., 1980, 58, 1281-1294. [all data]

Notes

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, References

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.