2
0
2010
kus
smi
0
journal
Original
Kustov, A. V.[Andrey V.]
Smirnova, N. L.[Nataliya L.]
J. Chem. Eng. Data
2010
2020-09-29
Standard Enthalpies and Heat Capacities of Solution of Urea and Tetramethylurea in Water
This paper presents the results of accurate measurements of the enthalpies of solution of a typical hydrophilic solute, urea, and its hydrophobic derivative, tetramethylurea, in water in the temperature range of (278.15 to 338.15) K. The standard enthalpies and heat capacities of solution are computed and compared with available literature values. Our results do indicate that the standard heat capacity of the solution of urea is very small, but it changes its sign at about the temperature minimum of the water heat capacity at constant pressure, while the heat capacity of tetramethylurea solution in water is large, positive, and independent of the temperature.
10.1021/je9010689
9
55
3055-3058
1
InChI=1S/ClH.K/h1H;/q;+1/p-1
WCUXLLCKKVVCTQ-UHFFFAOYSA-M
potassium chloride
ClK
1
Commercial source
2
InChI=1S/H2O/h1H2
XLYOFNOQVPJJNP-UHFFFAOYSA-N
water
H2O
1
Commercial source
1
Chemical reagent treatment
Fractional distillation
Chemical reagent treatment
Fractional distillation
2
99.99
4
Estimated by the compiler
3
InChI=1S/C3H8O/c1-2-3-4/h4H,2-3H2,1H3
BDERNNFJNOPAEC-UHFFFAOYSA-N
propan-1-ol
1-propanol
n-propanol
n-propyl alcohol
C3H8O
1
Commercial source
4
InChI=1S/CH4N2O/c2-1(3)4/h(H4,2,3,4)
XSQUKJJJFZCRTK-UHFFFAOYSA-N
urea
carbamide
carbamoylamine
CH4N2O
1
Commercial source
1
Dried in a desiccator
2
99.5
3
Estimated by the compiler
5
InChI=1S/C5H12N2O/c1-6(2)5(8)7(3)4/h1-4H3
AVQQQNCBBIEMEU-UHFFFAOYSA-N
tetramethylurea
1,1,3,3-tetramethylurea
N,N,N',N'-tetramethylurea
urea, 1,1,3,3-tetramethyl-
urea, tetramethyl
C5H12N2O
1
Commercial source
1
Fractional distillation
Molecular sieve treatment
Fractional distillation
Molecular sieve treatment
2
99.9
3
Gas chromatography
1
1
1
2
1
Principal objective of the work
VVD
TRC
3/3/2017
1
Molar enthalpy of solution, kJ/mol
CALVET:UFactor:0.5
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
2
Molality, mol/kg
1
Liquid
3
Pressure, kPa
Liquid
1
298.15
5
2
0.111
3
3
101
3
1
17.61
4
1
0.07
2
3
1
2
1
Principal objective of the work
ARR
TRC
9/27/2010
1
Molar enthalpy of solution, kJ/mol
OTHER:UFactor:0.5:sMethod:Ampoule calorimetery
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Liquid
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
2
Pressure, kPa
Liquid
3
Molality, mol/kg
3
Liquid
1
298.15
5
2
101.3
4
3
0
1
1
-10.18
4
1
0.07
3
4
1
2
1
Principal objective of the work
ARR
TRC
9/27/2010
1
Molar enthalpy of solution, kJ/mol
CALVET:UFactor:0.5
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Pressure, kPa
Liquid
101.3
4
1
Temperature, K
Liquid
2
Molality, mol/kg
4
Liquid
1
278.15
5
2
0
2
1
15.69
4
1
0.1
1
278.15
5
2
0.01596
4
1
15.66
4
1
0.1
1
278.15
5
2
0.02936
4
1
15.67
4
1
0.1
1
278.15
5
2
0.02945
4
1
15.72
4
1
0.1
1
278.15
5
2
0.03019
4
1
15.75
4
1
0.1
1
278.15
5
2
0.03582
4
1
15.67
4
1
0.1
1
283.15
5
2
0
2
1
15.6
4
1
0.1
1
283.15
5
2
0.01483
4
1
15.62
4
1
0.1
1
283.15
5
2
0.01644
4
1
15.58
4
1
0.1
1
283.15
5
2
0.01834
4
1
15.55
4
1
0.1
1
283.15
5
2
0.02161
4
1
15.64
4
1
0.1
1
283.15
5
2
0.03689
4
1
15.59
4
1
0.1
1
288.15
5
2
0
2
1
15.48
4
1
0.18
1
288.15
5
2
0.0216
4
1
15.41
4
1
0.18
1
288.15
5
2
0.02583
4
1
15.48
4
1
0.18
1
288.15
5
2
0.02856
4
1
15.49
4
1
0.18
1
288.15
5
2
0.06849
4
1
15.55
4
1
0.18
1
298.15
5
2
0
2
1
15.33
4
1
0.1
1
298.15
5
2
0.02231
4
1
15.36
4
1
0.1
1
298.15
5
2
0.02533
4
1
15.33
4
1
0.1
1
298.15
5
2
0.02877
4
1
15.28
4
1
0.1
1
298.15
5
2
0.03089
4
1
15.34
4
1
0.1
1
298.15
5
2
0.03598
4
1
15.39
4
1
0.1
1
298.15
5
2
0.03872
4
1
15.29
4
1
0.1
1
298.15
5
2
0.04804
4
1
15.32
4
1
0.1
1
298.15
5
2
0.04944
4
1
15.29
4
1
0.1
1
298.15
5
2
0.05257
4
1
15.31
4
1
0.1
1
298.15
5
2
0.0527
4
1
15.34
4
1
0.1
1
308.15
5
2
0
2
1
15.31
4
1
0.13
1
308.15
5
2
0.02048
4
1
15.33
4
1
0.13
1
308.15
5
2
0.02197
4
1
15.26
4
1
0.13
1
308.15
5
2
0.04933
4
1
15.35
4
1
0.13
1
308.15
5
2
0.05279
4
1
15.28
4
1
0.13
1
318.15
5
2
0
2
1
15.43
4
1
0.18
1
318.15
5
2
0.02435
4
1
15.36
4
1
0.18
1
318.15
5
2
0.02842
4
1
15.44
4
1
0.18
1
318.15
5
2
0.05136
4
1
15.5
4
1
0.18
1
318.15
5
2
0.08118
4
1
15.4
4
1
0.18
1
328.15
5
2
0
2
1
15.56
4
1
0.16
1
328.15
5
2
0.01547
4
1
15.6
4
1
0.16
1
328.15
5
2
0.02356
4
1
15.59
4
1
0.16
1
328.15
5
2
0.05128
4
1
15.53
4
1
0.16
1
328.15
5
2
0.05295
4
1
15.5
4
1
0.16
1
338.15
5
2
0
2
1
15.66
4
1
0.13
1
338.15
5
2
0.0312
4
1
15.68
4
1
0.13
1
338.15
5
2
0.03484
4
1
15.62
4
1
0.13
1
338.15
5
2
0.03717
4
1
15.64
4
1
0.13
1
338.15
5
2
0.07253
4
1
15.7
4
1
0.13
4
5
1
2
1
Principal objective of the work
ARR
TRC
9/27/2010
1
Molar enthalpy of solution, kJ/mol
CALVET:UFactor:0.5
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Liquid
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Pressure, kPa
Liquid
101.3
4
1
Temperature, K
Liquid
2
Molality, mol/kg
5
Liquid
1
278.15
5
2
0
2
1
-28.62
4
1
0.11
1
278.15
5
2
0.02303
4
1
-28.61
4
1
0.11
1
278.15
5
2
0.0373
4
1
-28.62
4
1
0.11
1
278.15
5
2
0.03927
4
1
-28.63
4
1
0.11
1
278.15
5
2
0.04241
4
1
-28.63
4
1
0.11
1
278.15
5
2
0.04511
4
1
-28.63
4
1
0.11
1
283.15
5
2
0
2
1
-27.53
4
1
0.13
1
283.15
5
2
0.02309
4
1
-27.5
4
1
0.13
1
283.15
5
2
0.03418
4
1
-27.57
4
1
0.13
1
283.15
5
2
0.03546
4
1
-27.51
4
1
0.13
1
283.15
5
2
0.03686
4
1
-27.52
4
1
0.13
1
283.15
5
2
0.03807
4
1
-27.56
4
1
0.13
1
288.15
5
2
0
2
1
-26.37
4
1
0.11
1
288.15
5
2
0.01812
4
1
-26.37
4
1
0.11
1
288.15
5
2
0.02115
4
1
-26.38
4
1
0.11
1
288.15
5
2
0.02712
4
1
-26.36
4
1
0.11
1
288.15
5
2
0.02945
4
1
-26.34
4
1
0.11
1
288.15
5
2
0.03713
4
1
-26.4
4
1
0.11
1
293.15
5
2
0
2
1
-25.31
4
1
0.13
1
293.15
5
2
0.02265
4
1
-25.27
4
1
0.13
1
293.15
5
2
0.0251
4
1
-25.31
4
1
0.13
1
293.15
5
2
0.02612
4
1
-25.34
4
1
0.13
1
293.15
5
2
0.02752
4
1
-25.34
4
1
0.13
1
293.15
5
2
0.03225
4
1
-25.3
4
1
0.13
1
298.15
5
2
0
2
1
-24.43
4
1
0.1
1
298.15
5
2
0.01917
4
1
-24.44
4
1
0.1
1
298.15
5
2
0.02785
4
1
-24.43
4
1
0.1
1
298.15
5
2
0.02933
4
1
-24.41
4
1
0.1
1
298.15
5
2
0.03789
4
1
-24.46
4
1
0.1
1
298.15
5
2
0.06223
4
1
-24.4
4
1
0.1
1
303.15
5
2
0
2
1
-23.45
4
1
0.1
1
303.15
5
2
0.02491
4
1
-23.43
4
1
0.1
1
303.15
5
2
0.02614
4
1
-23.43
4
1
0.1
1
303.15
5
2
0.03601
4
1
-23.47
4
1
0.1
1
303.15
5
2
0.04424
4
1
-23.45
4
1
0.1
1
303.15
5
2
0.05601
4
1
-23.45
4
1
0.1
1
308.15
5
2
0
2
1
-22.23
4
1
0.1
1
308.15
5
2
0.01019
4
1
-22.24
4
1
0.1
1
308.15
5
2
0.02043
4
1
-22.26
4
1
0.1
1
308.15
5
2
0.0227
4
1
-22.2
4
1
0.1
1
308.15
5
2
0.0504
4
1
-22.22
4
1
0.1
1
308.15
5
2
0.05496
4
1
-22.24
4
1
0.1
1
313.15
5
2
0
2
1
-21.17
4
1
0.12
1
313.15
5
2
0.02918
4
1
-21.19
4
1
0.12
1
313.15
5
2
0.03032
4
1
-21.16
4
1
0.12
1
313.15
5
2
0.03051
4
1
-21.15
4
1
0.12
1
313.15
5
2
0.05426
4
1
-21.14
4
1
0.12
1
313.15
5
2
0.05797
4
1
-21.21
4
1
0.12
1
318.15
5
2
0
2
1
-20.04
4
1
0.08
1
318.15
5
2
0.03031
4
1
-20.02
4
1
0.08
1
318.15
5
2
0.03086
4
1
-20.04
4
1
0.08
1
318.15
5
2
0.03211
4
1
-20.05
4
1
0.08
1
318.15
5
2
0.0349
4
1
-20.06
4
1
0.08
1
318.15
5
2
0.06247
4
1
-20.05
4
1
0.08
1
328.15
5
2
0
2
1
-18.14
4
1
0.07
1
328.15
5
2
0.03079
4
1
-18.13
4
1
0.07
1
328.15
5
2
0.03413
4
1
-18.13
4
1
0.07
1
328.15
5
2
0.03726
4
1
-18.14
4
1
0.07
1
328.15
5
2
0.03781
4
1
-18.16
4
1
0.07
1
328.15
5
2
0.06897
4
1
-18.15
4
1
0.07
1
338.15
5
2
0
2
1
-15.95
4
1
0.1
1
338.15
5
2
0.02166
4
1
-15.96
4
1
0.1
1
338.15
5
2
0.02838
4
1
-15.97
4
1
0.1
1
338.15
5
2
0.04375
4
1
-15.96
4
1
0.1
1
338.15
5
2
0.04753
4
1
-15.93
4
1
0.1
1
338.15
5
2
0.08974
4
1
-16
4
1
0.1