Pentanoic acid

• Formula: C₅H₁₀O₂
• Molecular weight: 102.1317
• IUPAC Standard InChI: InChI=1S/C5H10O2/c1-2-3-4-5(6)7/h2-4H2,1H3,(H,6,7) Copy

  
• IUPAC Standard InChIKey: NQPDZGIKBAWPEJ-UHFFFAOYSA-N Copy
• CAS Registry Number: 109-52-4
• 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: Valeric acid; n-Pentanoic acid; n-Valeric acid; Propylacetic acid; Valerianic acid; 1-Butanecarboxylic acid; n-C4H9COOH; Butanecarboxylic acid; Kyselina valerova; Valeric acid, normal; 1-Pentanoic acid; NSC 406833; Valeric acid, n-; NA 1760
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• Information on this page:
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Condensed phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Gas phase ion energetics data

Go To: Top, Condensed phase thermochemistry data, Mass spectrum (electron ionization), 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
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

C₅H₉O₂^- +  =

By formula: C₅H₉O₂^- + H⁺ = C₅H₁₀O₂

Mass spectrum (electron ionization)

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Adriaanse, Dekker, et al., 1965
Adriaanse, N.; Dekker, H.; Coops, J., Heats of combustion of normal saturated fatty acids and their methyl esters, Rec. Trav. Chim. Pays/Bas, 1965, 84, 393-407. [all data]

Lebedeva, 1964
Lebedeva, N.D., Heats of combustion of monocarboxylic acids, Russ. J. Phys. Chem. (Engl. Transl.), 1964, 38, 1435-1437. [all data]

Hancock, Watson, et al., 1954
Hancock, C.K.; Watson, G.M.; Gilby, R.F., Heats of combustion of five-carbon fatty acids and their methyl and ethyl esters, J. Phys. Chem., 1954, 58, 127-129. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Schjanberg, 1937
Schjanberg, E., Die verbrennungswarmen und die refraktionsdaten einiger pentensaureeste, Z. Phys. Chem., 1937, 178, 274-281. [all data]

McDougall and Kilpatrick, 1965
McDougall, L.A.; Kilpatrick, J.E., Entropy and related thermodynamic properties of n-valeric acid, J. Chem. Phys., 1965, 42, 2307-2310. [all data]

Skuratov and Bonetskaya, 1966
Skuratov, S.M.; Bonetskaya, A.K., Enthalpy of formation of amide bonds, Polym. Sci. USSR (Engl. Transl.), 1966, 8, 1754-1757. [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]

Watanabe, Yokoyama, et al., 1973
Watanabe, I.; Yokoyama, Y.; Ikeda, S., Lone pair ionization potentials of carboxylic acids determined by He(I) photoelectron spectroscopy, Bull. Chem. Soc. Jpn., 1973, 46, 1959. [all data]

Audier, Milliet, et al., 1985
Audier, H.; Milliet, A.; Sozzi, G., Isomerisation des cation radicaux acides pentanoique et methyl-3-butanoique in phase gazeuse, Bull. Soc. Chim. France, 1985, 5, 833. [all data]

Holmes and Lossing, 1980
Holmes, J.L.; Lossing, F.P., Thermochemistry and unimolecular reactions of ionized acetic acid and its enol in the gas phase., J. Am. Chem. Soc., 1980, 102, 3732. [all data]

Holmes and Lossing, 1980, 2
Holmes, J.L.; Lossing, F.P., Gas-phase heats of formation of keto and enol ions of carbonyl compounds., J. Am. Chem. Soc., 1980, 102, 1591. [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]

McLuckey, Cameron, et al., 1981
McLuckey, S.A.; Cameron, D.; Cooks, R.G., Proton affinities from the dissociation of proton bound dimers, J. Am. Chem. Soc., 1981, 103, 1313. [all data]

Notes

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  S°liquid	Entropy of liquid at standard conditions
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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