Thioacetic acid
- Formula: C2H4OS
- Molecular weight: 76.118
- IUPAC Standard InChI: InChI=1S/C2H4OS/c1-2(3)4/h1H3,(H,3,4)
- IUPAC Standard InChIKey: DUYAAUVXQSMXQP-UHFFFAOYSA-N
- CAS Registry Number: 507-09-5
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Methanecarbothiolic acid; Thioacetic S-acid; Ethanethioic acid; Acetyl mercaptan; Ethanethiolic acid; Thiacetic acid; Thiolacetic acid; Thionoacetic acid; CH3COSH; Kyselina thiooctova; UN 2436; USAF EK-P-737; Acetic acid, thio-
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Condensed phase thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | -52.42 ± 0.35 | kcal/mol | Ccr | Sunner, 1963 | Correction of Sunner, 1955 |
| ΔfH°liquid | -51.74 ± 0.14 | kcal/mol | Cm | Sunner and Wadso, 1957 | Reanalyzed by Cox and Pilcher, 1970, Original value = -51.5 ± 0.4 kcal/mol; Heat of hydrolysis |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -416.22 | kcal/mol | Ccr | Sunner, 1963 | Correction of Sunner, 1955 |
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 by: William E. Acree, Jr., James S. Chickos
Enthalpy of vaporization
| ΔvapH (kcal/mol) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 8.41 | 333. | Dykyj, Svoboda, et al., 1999 | Based on data from 307. to 360. K. |
Reaction thermochemistry 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 by: 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: C4H6O2S = C2H2O + C2H4OS
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 22.6 | kcal/mol | Eqk | Blake and Speis, 1974 | gas phase; Heat of formation derived by 77PED/RYL |
+
=
+
By formula: C2H4OS + H2O = C2H4O2 + H2S
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -0.64 ± 0.07 | kcal/mol | Cm | Sunner and Wadso, 1957 | liquid phase; Heat of hydrolysis |
+
=
By formula: C2H4OS + C3H6O = C5H10O2S
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -6.5 ± 0.2 | kcal/mol | Eqk | Horii, Kawamura, et al., 1972 | liquid phase; solvent: CD3COCD3; NMR |
+
=
By formula: C2H2O + C2H4OS = C4H6O2S
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -22.6 | kcal/mol | Eqk | Blake and Speis, 1974 | gas phase |
Gas phase ion energetics 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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
View reactions leading to C2H4OS+ (ion structure unspecified)
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 10.06 | PE | Nagata, Yamabe, et al., 1975 | Vertical value; LLK |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, 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.
Sunner, 1963
Sunner, S.,
Corrected heat of combustion and formation values for a number of organic sulphur compounds,
Acta Chem. Scand., 1963, 17, 728-730. [all data]
Sunner, 1955
Sunner, S.,
Thermochemical investigations on organic sulfur compounds. V. On the resonance energy of thiolacetic acid, thiourea, thiosemicarbzaide, thiophene and thianthrene,
Acta Chem. Scand., 1955, 9, 847-854. [all data]
Sunner and Wadso, 1957
Sunner, S.; Wadso, I.,
The heat of hydrolysis of thiolacetic acid,
Trans. Faraday Soc., 1957, 53, 455-459. [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]
Dykyj, Svoboda, et al., 1999
Dykyj, J.; Svoboda, J.; Wilhoit, R.C.; Frenkel, M.L.; Hall, K.R.,
Vapor Pressure of Chemicals: Part A. Vapor Pressure and Antoine Constants for Hydrocarbons and Sulfur, Selenium, Tellurium and Hydrogen Containing Organic Compounds, Springer, Berlin, 1999, 373. [all data]
Blake and Speis, 1974
Blake, P.G.; Speis, A.,
Reactions of keten. Part IV. Kinetics and thermodynamics of the gas-phase reaction: Thioacetic acid + keten = acetic Thioanhydride,
J. Chem. Soc. Perkin Trans. 2, 1974, 1879-1881. [all data]
Horii, Kawamura, et al., 1972
Horii, T.; Kawamura, S.; Tsurugi, J.,
A NMR study of the thioacetic acid-acetone mixture,
Bull. Chem. Soc. Jpn., 1972, 45, 2200-2202. [all data]
Nagata, Yamabe, et al., 1975
Nagata, S.; Yamabe, T.; Fukui, K.,
A study of the electronic spectra of thioacetic acid and its ethyl ester,
J. Phys. Chem., 1975, 79, 2335. [all data]
Notes
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- Symbols used in this document:
ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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