Barbituric acid
- Formula: C4H4N2O3
- Molecular weight: 128.0862
- IUPAC Standard InChI: InChI=1S/C4H4N2O3/c7-2-1-3(8)6-4(9)5-2/h1H2,(H2,5,6,7,8,9)
- IUPAC Standard InChIKey: HNYOPLTXPVRDBG-UHFFFAOYSA-N
- CAS Registry Number: 67-52-7
- Chemical structure:
This structure is also available as a 2d Mol file - Species with the same structure:
- Other names: 2,4,6(1H,3H,5H)-Pyrimidinetrione; Malonylurea; Pyrimidinetrione; Urea, N,N'-(1,3-dioxo-1,3-propanediyl)-; 2,4,6-Pyrimidinetriol; 2,4,6-Trihydroxypyrimidine; 2,4,6-Trioxohexahydropyrimidine; 6-Hydroxyuracil; 2,4,6-Pyrimidinetrione(1H,3H,5H)
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- Other data available:
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Condensed phase thermochemistry data
Go To: Top, Phase change 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°solid | -151.70 ± 0.68 | kcal/mol | Ccb | Soldatova, Kabo, et al., 1990 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -361.16 ± 0.68 | kcal/mol | Ccb | Soldatova, Kabo, et al., 1990 | ALS |
| ΔcH°solid | -358.89 | kcal/mol | Ccb | Lemoult, 1904 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid,1 bar | 37.60 | cal/mol*K | N/A | Soldatova, Kabo, et al., 1990, 2 | DH |
| S°solid,1 bar | 37.67 | cal/mol*K | N/A | Koshchenko, Ismailov, et al., 1985 | Extrapolated below 90 K.; DH |
Constant pressure heat capacity of solid
| Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 33.72 | 298.15 | Soldatova, Kabo, et al., 1990, 2 | T = 10 to 450 K. Cp(c) = 25.67 + 0.3361T + 3.382x10-4T2 - 5.64x10-7T3 J/mol*K (200 to 450 K).; DH |
| 33.72 | 298.15 | Koshchenko, Ismailov, et al., 1985 | T = 90 to 300 K.; DH |
Phase change data
Go To: Top, Condensed phase 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: William E. Acree, Jr., James S. Chickos
Enthalpy of sublimation
| ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 27.0 ± 0.96 | 442. | TE | Brunetti and Piacente, 1999 | Based on data from 392. to 493. K. |
| 26.60 ± 0.07 | 294. to 438. | GS | Zielenkiewicz, Perlovich, et al., 1999 | |
| 29.47 ± 0.41 | 440. | ME | Soldatova, Kabo, et al., 1990, 3 | Based on data from 404. to 479. K. |
Enthalpy of fusion
| ΔfusH (kcal/mol) | Temperature (K) | Reference |
|---|---|---|
| 4.988 | 526.4 | Roux, Temprado, et al., 2008 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Soldatova, Kabo, et al., 1990
Soldatova, T.V.; Kabo, G.Ya.; Kozyro, A.A.; Frenkel, M.L.,
Thermodynamic properties and tautomerism of barbituric acid,
Russ. J. Phys. Chem. (Engl. Transl.), 1990, 64, 177-180. [all data]
Lemoult, 1904
Lemoult, M.P.,
Remarques sur une serie recenie de determinations calorimetriques,
Compt. Rend., 1904, 663-635. [all data]
Soldatova, Kabo, et al., 1990, 2
Soldatova, T.V.; Kabo, G.Ya.; Kozyro, A.A.; Frenkel, M.L.,
Thermodynamic properties and tautomerism of barbituric acid,
Zhur. Fiz. Khim., 1990, 64(2), 336-343. [all data]
Koshchenko, Ismailov, et al., 1985
Koshchenko, V.I.; Ismailov, T.S.; Potekhin, V.M.; Razikov, K.Kh.,
Thermodynamic functions of barbituric acid,
Zhur. Prikl. Khim. (Leningrad), 1985, 58, 445-456. [all data]
Brunetti and Piacente, 1999
Brunetti, B.; Piacente, V.,
Sublimation Enthalpies Study for Barbituric, Tiobarbituric, and Selenobarbituric Acids from Their Vapor Pressure Measurements,
J. Chem. Eng. Data, 1999, 44, 4, 809-812, https://doi.org/10.1021/je980300k
. [all data]
Zielenkiewicz, Perlovich, et al., 1999
Zielenkiewicz, X.; Perlovich, G.L.; Wszelaka-Rylik, M.,
Journal of Thermal Analysis and Calorimetry, 1999, 57, 1, 225-234, https://doi.org/10.1023/A:1010179814511
. [all data]
Soldatova, Kabo, et al., 1990, 3
Soldatova, T.V.; Kabo, G.Ya.; Kozyro, A.A.; Frenkel, M.L.,
Thermodynamic properties and tautomerism of barbituric acid,
Zh. Fiz. Khim., 1990, 64, 2, 336. [all data]
Roux, Temprado, et al., 2008
Roux, Maria Victoria; Temprado, Manuel; Notario, Rafael; Foces-Foces, Concepcion; Emel'yanenko, Vladimir N.; Verevkin, Sergey P.,
Structure-Energy Relationship in Barbituric Acid: A Calorimetric, Computational, and Crystallographic Study,
J. Phys. Chem. A, 2008, 112, 32, 7455-7465, https://doi.org/10.1021/jp803370u
. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid S°solid,1 bar Entropy of solid at standard conditions (1 bar) ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔfusH Enthalpy of fusion ΔsubH Enthalpy of sublimation - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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