Enthalpies and entropies of melting from differential scanning calorimetry and freezing point depressions: urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, tetramethylurea, and thiourea
作者： T.A. Zordan , D.G. Hurkot , M. Peterson , L.G. Hepler
DOI: 10.1016/0040-6031(72)80014-5
关键词:
摘要: Abstract The following enthalpies of melting have been determined with a differential scanning calorimeter: urea, 3.22 kcal mole −1 ; 1,3-dimethylurea, 2.97 methylurea, 3.34 : 1,1-dimethylurea, 5.49 thiourea, 3.30 . Freezing point depression measurements led to the melting: benzoic acid, 4.29 3.11 tetramethylurea, 3.37 results above lead entropies 8.00 cal deg 8.90 12.06 7.95 12.39 7.28
elsevier.com
sci-hub.se 参考文章(6)
R. H. Stokes, Osmotic Coefficients of Concentrated Aqueous Urea Solutions from Freezing-Point Measurements The Journal of Physical Chemistry. ,vol. 70, pp. 1199- 1203 ,(1966) , 10.1021/J100876A038
F. W. Miller, H. R. Dittmar, The Solubility of Urea in Water. The Heat of Fusion of Urea Journal of the American Chemical Society. ,vol. 56, pp. 848- 849 ,(1934) , 10.1021/JA01319A023
William John Howells, CXIX.—The binary system carbamide-ammonium nitrate. Molecular association in each component Journal of The Chemical Society (resumed). pp. 910- 915 ,(1929) , 10.1039/JR9290000910
William John Howells, CCLX.—The ternary system carbamide–ammonium nitrate–sodium nitrate J. Chem. Soc.. ,vol. 0, pp. 2010- 2017 ,(1930) , 10.1039/JR9300002010
William John Howells, CCCCXLVI.—Binary systems comprising carbamide with certain metallic nitrates Journal of The Chemical Society (resumed). pp. 3208- 3212 ,(1931) , 10.1039/JR9310003208
G.T. Furukawa, R.E. Mccoskey, G.J. King, Calorimetric properties of benzoic acid from 0-degrees to 410-degrees-K Journal of research of the National Bureau of Standards. ,vol. 47, pp. 256- ,(1951) , 10.6028/JRES.047.032