Urea

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, References, Notes

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

Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfgas-235.5 ± 1.2kJ/molCcbKabo, Miroshnichenko, et al., 1990see Simirsky, Kabo, et al., 1987

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, 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
Δfsolid-333.11 ± 0.69kJ/molCcbKabo, Miroshnichenko, et al., 1990see Simirsky, Kabo, et al., 1987; ALS
Δfsolid-320.2 ± 2.0kJ/molCcbContineanu, Wagner, et al., 1982ALS
Δfsolid-333.39 ± 0.17kJ/molCcbJohnson, 1975ALS
Δfsolid-333.3 ± 0.2kJ/molCcbHuffman, 1940ALS
Δfsolid-323.6kJ/molCcbSchmidt and Becker, 1933ALS
Quantity Value Units Method Reference Comment
Δcsolid-635. ± 8.kJ/molAVGN/AAverage of 8 values; Individual data points
Quantity Value Units Method Reference Comment
solid,1 bar104.26J/mol*KN/AAndersson, Matsuo, et al., 1993DH
solid,1 bar104.93J/mol*KN/AKozyro, Dalidovich, et al., 1986DH
solid,1 bar105.4J/mol*KN/AParks, Huffman, et al., 1933Extrapolation below 90 K, 33.18 J/mol*K.; DH
solid,1 bar172.J/mol*KN/AGibson, Latimer, et al., 1920Extrapolation below 86 K, no details.; DH

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
92.79298.15Andersson, Matsuo, et al., 1993T = 15 to 310 K.; DH
94.0304.7Gambino and Bros, 1988T = 303 to 413 K.; DH
93.08298.15Kozyro, Dalidovich, et al., 1986T = 5 to 400 K. Cp = 38.43 + 4.98x10-2T + 7.05x10-4T2 - 8.61x10-7T3 (240 to 400 K).; DH
90.0298.15Sasaki and Yokotake, 1966T = 90 to 298 K.; DH
93.14298.15Ruehrwein and Huffman, 1946T = 19 to 318 K.; DH
68.6293.Campbell and Campbell, 1940DH
93.64298.0Parks, Huffman, et al., 1933T = 93 to 298 K. Value is unsmoothed experimental datum.; DH
115.5298.0Gibson, Latimer, et al., 1920T = 86 to 300 K. Value is unsmoothed experimental datum.; DH

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, 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
MM - Michael M. Meot-Ner (Mautner)
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Proton affinity at 298K

Proton affinity (kJ/mol) Reference Comment
868.4 ± 2.5Zheng and Cooks, 2002MM
873.5 ± 5.0Wang, Ma, et al., 1998m-bromoaniline; p-fluorobenzamide; MM
873.5 ± 5.0Wang, Ma, et al., 1998T = T(eff) = 410-560 KK; Acrylamide;m-Bromoaniline; MM

Gas basicity at 298K

Gas basicity (review) (kJ/mol) Reference Comment
838.7 ± 3.0Zheng and Cooks, 2002MM
846.1 ± 5.0Wang, Ma, et al., 1998m-bromoaniline; p-fluorobenzamide; MM
841.6 ± 5.0Wang, Ma, et al., 1998T = T(eff) = 410-560 KK; Acrylamide;m-Bromoaniline; MM

Protonation entropy at 298K

Protonation entropy (J/mol*K) Reference Comment
9.4Zheng and Cooks, 2002MM
-1.9Wang, Ma, et al., 1998T = T(eff) = 410-560 KK; Acrylamide;m-Bromoaniline; MM

Ionization energy determinations

IE (eV) Method Reference Comment
9.7PEDebies and Rabalais, 1974LLK
10.27 ± 0.05EIBaldwin, Kirkien-Konasiewicz, et al., 1966RDSH
9.8PEBieri, Asbrink, et al., 1982Vertical value; LBLHLM
10.28PEDougherty, Wittel, et al., 1976Vertical value; LLK
10.33PEMines and Thompson, 1975Vertical value; LLK
10.15PEMeeks, Arnett, et al., 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH2NO+12.90?EILoudon and Webb, 1977LLK

De-protonation reactions

CH3N2O- + Hydrogen cation = Urea

By formula: CH3N2O- + H+ = CH4N2O

Quantity Value Units Method Reference Comment
Δr1514. ± 12.kJ/molCIDCMa, Wang, et al., 1998gas phase; H and S (20.5±1.8 eu) directly from kinetic method; B
Δr1517. ± 11.kJ/molG+TSTaft, 1987gas phase; value altered from reference due to change in acidity scale; B
Δr1495. ± 8.8kJ/molEIAEMuftakhov, Vasil'ev, et al., 1999gas phase; B
Quantity Value Units Method Reference Comment
Δr1488. ± 13.kJ/molH-TSMa, Wang, et al., 1998gas phase; H and S (20.5±1.8 eu) directly from kinetic method; B
Δr1487. ± 10.kJ/molIMRETaft, 1987gas phase; value altered from reference due to change in acidity scale; B

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics 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]

Zheng and Cooks, 2002
Zheng, X.; Cooks, R.G., Thermochemical determinations by the kinetic method with direct entropy corrrection, J. Phys. Chem. A, 2002, 106, 9939. [all data]

Wang, Ma, et al., 1998
Wang, F.; Ma, S.G.; Zhang, D.X.; Cooks, R.G., Proton affinity and gas-phase basicity of urea, J. Phys. Chem. A., 1998, 102, 2988. [all data]

Debies and Rabalais, 1974
Debies, T.P.; Rabalais, J.W., Electronic structure of amino acids and ureas, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 315. [all data]

Baldwin, Kirkien-Konasiewicz, et al., 1966
Baldwin, M.; Kirkien-Konasiewicz, A.; Loudon, A.G.; Maccoll, A.; Smith, D., Localised or delocalised charges in molecule-ions?, Chem. Commun., 1966, 574. [all data]

Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]

Dougherty, Wittel, et al., 1976
Dougherty, D.; Wittel, K.; Meeks, J.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Ureas, uracils, and thymine, J. Am. Chem. Soc., 1976, 98, 3815. [all data]

Mines and Thompson, 1975
Mines, G.W.; Thompson, H.W., The photoelectron spectra of amides, thioamides, ureas and thioureas, Spectrochim. Acta, 1975, 31, 137. [all data]

Meeks, Arnett, et al., 1975
Meeks, J.L.; Arnett, J.F.; Larson, D.B.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Urea, oxamide, oxalic acid and oxamic acid, J. Am. Chem. Soc., 1975, 97, 3905. [all data]

Loudon and Webb, 1977
Loudon, A.G.; Webb, K.S., The nature of the [C2H6N]+ and [CH4N]+ ions formed by electron impact on methylated formamides, acetamides, ureas, thioureas and hexamethylphosphoramide, Org. Mass Spectrom., 1977, 12, 283. [all data]

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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References