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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Reaction 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:
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
CH3N2O- + =
By formula: CH3N2O- + H+ = CH4N2O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 361.8 ± 2.8 | kcal/mol | CIDC | Ma, Wang, et al., 1998 | gas phase; H and S (20.5±1.8 eu) directly from kinetic method; B |
| ΔrH° | 362.5 ± 2.6 | kcal/mol | G+TS | Taft, 1987 | gas phase; value altered from reference due to change in acidity scale; B |
| ΔrH° | 357.4 ± 2.1 | kcal/mol | EIAE | Muftakhov, Vasil'ev, et al., 1999 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 355.7 ± 3.2 | kcal/mol | H-TS | Ma, Wang, et al., 1998 | gas phase; H and S (20.5±1.8 eu) directly from kinetic method; B |
| ΔrG° | 355.5 ± 2.5 | kcal/mol | IMRE | Taft, 1987 | gas phase; value altered from reference due to change in acidity scale; B |
+
=
By formula: CH4N2O + C4H4O2 = N-(aminocarbonyl)-3-oxobutyramide
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -25.43 | kcal/mol | Kin | Lopatin, Popov, et al., 1992 | liquid phase; solvent: Solution; ALS |
6 =
+ 3
+ 6
By formula: 6CH4N2O = C3H6N6 + 3CO2 + 6H3N
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 112.2 | kcal/mol | Eqk | Rukevich and Zagranichnyi, 1971 | liquid phase; ALS |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Ma, Wang, et al., 1998
Ma, S.G.; Wang, F.; Cooks, R.G.,
Gas-phase acidity of urea,
J. Mass Spectrom., 1998, 33, 10, 943-949, https://doi.org/10.1002/(SICI)1096-9888(1998100)33:10<943::AID-JMS703>3.0.CO;2-B
. [all data]
Taft, 1987
Taft, R.W.,
The Nature and Analysis of Substitutent Electronic Effects,
Personal communication. See also Prog. Phys. Org. Chem., 1987, 16, 1. [all data]
Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Mazunov, V.A.,
Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry,
Rapid Commun. Mass Spectrom., 1999, 13, 12, 1104-1108, https://doi.org/10.1002/(SICI)1097-0231(19990630)13:12<1104::AID-RCM619>3.0.CO;2-C
. [all data]
Lopatin, Popov, et al., 1992
Lopatin, E.B.; Popov, V.V.; Epshtein, N.A.; Mikhaleva, L.M.; Makarov, Yu.N.,
Kinetic and thermochemical characteristics of diketene-based reactions,
Khim.-Farm. Zh., 1992, 26, 76-78. [all data]
Rukevich and Zagranichnyi, 1971
Rukevich, O.S.; Zagranichnyi, V.I.,
Equilibrium in the reaction of melamine formation from urea,
J. Anal. Chem. USSR, 1971, 44, 1616-1620. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
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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