Pentanoic acid
- Formula: C5H10O2
- Molecular weight: 102.1317
- IUPAC Standard InChIKey: NQPDZGIKBAWPEJ-UHFFFAOYSA-N
- 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
The 3d structure may be viewed using Java or Javascript. - 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
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
- NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
- 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.
Reaction thermochemistry data
Go To: Top, 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 as indicated in comments:
B - John E. Bartmess
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
C5H9O2- + =
By formula: C5H9O2- + H+ = C5H10O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 346.2 ± 2.1 | kcal/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrH° | 346.1 ± 2.4 | kcal/mol | G+TS | McLuckey, Cameron, et al., 1981 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 339.2 ± 2.0 | kcal/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrG° | 339.1 ± 2.3 | kcal/mol | CIDC | McLuckey, Cameron, et al., 1981 | gas phase; B |
By formula: 2H2 + C5H6O2 = C5H10O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -65.8 ± 1.2 | kcal/mol | Chyd | Flitcroft and Skinner, 1958 | liquid phase; ALS |
Gas phase ion energetics data
Go To: Top, 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 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
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.53 | PE | Watanabe, Yokoyama, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C2H4O2+ | 10.8 ± 0.1 | C3H6 | EI | Audier, Milliet, et al., 1985 | LBLHLM |
C2H5O2+ | 10.4 ± 0.1 | C3H5 | EI | Audier, Milliet, et al., 1985 | LBLHLM |
C2H402+ | 10.56 ± 0.05 | C3H6 | EI | Holmes and Lossing, 1980 | LLK |
C2H402+ | 10.56 | C3H6 | EI | Holmes and Lossing, 1980, 2 | LLK |
De-protonation reactions
C5H9O2- + =
By formula: C5H9O2- + H+ = C5H10O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 346.2 ± 2.1 | kcal/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrH° | 346.1 ± 2.4 | kcal/mol | G+TS | McLuckey, Cameron, et al., 1981 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 339.2 ± 2.0 | kcal/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrG° | 339.1 ± 2.3 | kcal/mol | CIDC | McLuckey, Cameron, et al., 1981 | gas phase; B |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Flitcroft and Skinner, 1958
Flitcroft, T.L.; Skinner, H.A.,
Heats of hydrogenation Part 2.-Acetylene derivatives,
Trans. Faraday Soc., 1958, 54, 47-53. [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]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy 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
- 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.