Urea

• Formula: CH₄N₂O
• Molecular weight: 60.0553
• IUPAC Standard InChI: InChI=1S/CH4N2O/c2-1(3)4/h(H4,2,3,4) Copy

  
• IUPAC Standard InChIKey: XSQUKJJJFZCRTK-UHFFFAOYSA-N Copy
• 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
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• 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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• Information on this page:
  • Normal melting point
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
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Normal melting point

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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: Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

References

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

DellaGatta and Ferro, 1987
DellaGatta, G.; Ferro, D., Enthalpies of fusion and solid-to-solid transition, entropies of fusion for urea and twelve alkylurea, Thermochim. Acta, 1987, 122, 143-52. [all data]

El-Banna, 1978
El-Banna, H.M., Solid Dispersion of Pharmaceutaical Ternary Systems I. Phase Diagrams of Aspirin- Acetominophen-Urea Systems, J. Pharm. Sci., 1978, 67, 1109. [all data]

Zordan, Hurkot, et al., 1972
Zordan, T.A.; Hurkot, D.G.; Peterson, M.; Hepler, L.G., Enthalpies and entropies of melting from differential scanning calorimetry and freezing point depressions: urea, methylurea, 1, 1-dimethylurea, 1, 3- dimethylurea, tetramethylurea, and thiourea, Thermochim. Acta, 1972, 5, 21. [all data]

Boje and Hvidt, 1971
Boje, L.; Hvidt, A., Densities of aqueous mixtures of non-electrolytes, J. Chem. Thermodyn., 1971, 3, 663. [all data]

Miller and Dittmar, 1934
Miller, F.W.; Dittmar, H.R., The Solubility of Urea in Water. The Heat of Fusion of Urea, J. Am. Chem. Soc., 1934, 56, 848-9. [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, 7, 2733, https://doi.org/10.1021/ja01334a016 . [all data]

Pushin and Sladovic, 1928
Pushin, N.A.; Sladovic, L., Equilibrium in the binary systems cresols-amines, J. Chem. Soc., 1928, 1928, 2474. [all data]

Buechner, 1906
Buechner, E.H., Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1906, 54, 665. [all data]

Notes

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• Symbols used in this document:
  

  Tfus	Fusion (melting) point

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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