Urea
- Formula: CH4N2O
- Molecular weight: 60.0553
- IUPAC Standard InChI: InChI=1S/CH4N2O/c2-1(3)4/h(H4,2,3,4)
- IUPAC Standard InChIKey: XSQUKJJJFZCRTK-UHFFFAOYSA-N
- CAS Registry Number: 57-13-6
- 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: Carbamide; Carbamimidic acid; Carbonyldiamide; Isourea; Pseudourea; Urea-13C; Ureaphil; Ureophil; Urevert; UR; (NH2)2CO; Carbonyl Diamine; Alphadrate; Aquacare; Aquadrate; B-I-K; Calmurid; Carbaderm; Keratinamin; NCI-C02119; Pastaron; Prespersion, 75 urea; Ultra Mide; Urepearl; Mocovina; Supercel 3000; Varioform II; Benural 70; Harnstoff; Basodexan; Bubber shet; Elaqua xx; Hyanit; Nutraplus; Onychomal; NSC 34375; Uroderm; Panafil (Salt/Mix); Cerovel (Salt/Mix); component of Artra Ashy Skin Cream (Salt/Mix)
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Condensed phase thermochemistry data
Go To: Top, 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 | -79.62 ± 0.16 | kcal/mol | Ccb | Kabo, Miroshnichenko, et al., 1990 | see Simirsky, Kabo, et al., 1987; ALS |
| ΔfH°solid | -76.52 ± 0.48 | kcal/mol | Ccb | Contineanu, Wagner, et al., 1982 | ALS |
| ΔfH°solid | -79.682 ± 0.041 | kcal/mol | Ccb | Johnson, 1975 | ALS |
| ΔfH°solid | -79.67 ± 0.05 | kcal/mol | Ccb | Huffman, 1940 | ALS |
| ΔfH°solid | -77.34 | kcal/mol | Ccb | Schmidt and Becker, 1933 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -152. ± 2. | kcal/mol | AVG | N/A | Average of 8 values; Individual data points |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid,1 bar | 24.919 | cal/mol*K | N/A | Andersson, Matsuo, et al., 1993 | DH |
| S°solid,1 bar | 25.079 | cal/mol*K | N/A | Kozyro, Dalidovich, et al., 1986 | DH |
| S°solid,1 bar | 25.19 | cal/mol*K | N/A | Parks, Huffman, et al., 1933 | Extrapolation below 90 K, 33.18 J/mol*K.; DH |
| S°solid,1 bar | 41.1 | cal/mol*K | N/A | Gibson, Latimer, et al., 1920 | Extrapolation below 86 K, no details.; DH |
Constant pressure heat capacity of solid
| Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 22.18 | 298.15 | Andersson, Matsuo, et al., 1993 | T = 15 to 310 K.; DH |
| 22.5 | 304.7 | Gambino and Bros, 1988 | T = 303 to 413 K.; DH |
| 22.25 | 298.15 | Kozyro, Dalidovich, et al., 1986 | T = 5 to 400 K. Cp = 38.43 + 4.98x10-2T + 7.05x10-4T2 - 8.61x10-7T3 (240 to 400 K).; DH |
| 21.5 | 298.15 | Sasaki and Yokotake, 1966 | T = 90 to 298 K.; DH |
| 22.26 | 298.15 | Ruehrwein and Huffman, 1946 | T = 19 to 318 K.; DH |
| 16.4 | 293. | Campbell and Campbell, 1940 | DH |
| 22.38 | 298.0 | Parks, Huffman, et al., 1933 | T = 93 to 298 K. Value is unsmoothed experimental datum.; DH |
| 27.61 | 298.0 | Gibson, Latimer, et al., 1920 | T = 86 to 300 K. Value is unsmoothed experimental datum.; DH |
References
Go To: Top, Condensed phase thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Kabo, Miroshnichenko, et al., 1990
Kabo, G.Ya.; Miroshnichenko, E.A.; Frenkel, M.L.; Kozyro, A.A.; Simirskii, V.V.; Krasulin, A.P.; Vorob'eva, V.P.; Lebedev, Yu.A.,
Thermochemistry of urea alkyl derivatives,
Bull. Acad. Sci. USSR, Div. Chem. Sci., 1990, 662-667. [all data]
Simirsky, Kabo, et al., 1987
Simirsky, V.V.; Kabo, G.J.; Frenkel, M.L.,
Additivity of the enthalpies of formation of urea derivatives in the crystalline state,
J. Chem. Thermodyn., 1987, 19, 1121-1127. [all data]
Contineanu, Wagner, et al., 1982
Contineanu, I.; Wagner, L.; Stanescu, L.; Marchidan, D.I.,
Combustion and formation enthalpies of o-phenylenediamine, urea and 2-benzimidazolone,
Rev. Roum. Chim., 1982, 27, 205-209. [all data]
Johnson, 1975
Johnson, W.H.,
The enthalpies of combustion and formation of acetanilide and urea,
J. Res. NBS, 1975, 79, 487-491. [all data]
Huffman, 1940
Huffman, H.M.,
Thermal Data. XII. The heats of combustion of urea and guanidine carbonate and their standard free energies of formation,
J. Am. Chem. Soc., 1940, 62, 1009-1011. [all data]
Schmidt and Becker, 1933
Schmidt, V.A.; Becker, F.,
Die Bildungswarme von Nitrocellulofen, Nitroglycerin und anderen widuigen Beltandteilen von Treibmitteln,
Z. Gesamte Schiess Sprengstoffwes., 1933, 33, 280-282. [all data]
Andersson, Matsuo, et al., 1993
Andersson, O.; Matsuo, T.; Suga, H.; Ferloni, P.,
Low-temperature heat capacity of urea,
Int. J. Thermophys., 1993, 14(1), 149-158. [all data]
Kozyro, Dalidovich, et al., 1986
Kozyro, A.A.; Dalidovich, S.V.; Krasulin, A.P.,
Heat capacity, enthalpy of fusion, and thermodynamic properties of urea,
Zhur. Prikl. Khim. (Leningrad), 1986, 59, 1456-1459. [all data]
Parks, Huffman, et al., 1933
Parks, G.S.; Huffman, H.M.; Barmore, M.,
Thermal data on organic compounds. XI. The heat capacities,
entropies and free energies of ten compounds containing oxygen or nitrogen. J. Am. Chem. Soc., 1933, 55, 2733-2740. [all data]
Gibson, Latimer, et al., 1920
Gibson, G.E.; Latimer, W.M.; Parks, G.S.,
Entropy changes at low temperatures. I. Formic acid and urea. A test of the third law of thermodynamics,
J. Am. Chem. Soc., 1920, 42, 1533-1542. [all data]
Gambino and Bros, 1988
Gambino, M.; Bros, J.P.,
Capacite calorifique de l'uree et de quelques melanges eutectiques a base d'uree entre 30 et 140°C,
Thermochim. Acta, 1988, 127, 223-236. [all data]
Sasaki and Yokotake, 1966
Sasaki, K.; Yokotake, T.,
Thermodynamic properties of the products in SO3-NH3 reaction. II. Specific heats of sulfamide and ammonium sulfamate,
Tokyo Kogyo Shikenshi Hokohu, 1966, 61, 309-314. [all data]
Ruehrwein and Huffman, 1946
Ruehrwein, R.A.; Huffman, H.M.,
Thermal data. XIX. The heat capacity, entropy and free energy of urea,
J. Am. Chem. Soc., 1946, 68, 1759-1761. [all data]
Campbell and Campbell, 1940
Campbell, A.N.; Campbell, A.J.R.,
The heats of solution, heats of formation,
specific heats and equilibrium diagrams of certain molecular compounds. J. Am. Chem. Soc., 1940, 62, 291-297. [all data]
Notes
Go To: Top, Condensed phase thermochemistry 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 - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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