Home Symbol which looks like a small house Up Solid circle with an upward pointer in it

1H-Pyrazole

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Reaction 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Deltafgas177.4kJ/molN/AZaheeruddin and Lodhi, 1991Value computed using «DELTA»fHsolid° value of 112.4 kj/mol from Zaheeruddin and Lodhi, 1991 and «DELTA»subH° value of 65.0 kj/mol from Jimenez, Roux, et al., 1987.; DRB
Deltafgas179.4 ± 0.8kJ/molCcbJimenez, Roux, et al., 1987see Jimenez, Roux, et al., 1986; ALS
Deltafgas181. ± 8.8kJ/molCcbBedford, Edmondson, et al., 1962ALS

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Reaction 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:
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
Deltafsolid  CcbZaheeruddin and Lodhi, 1991uncertain value: 112.38 kJ/mol; ALS
Deltafsolid105.4 ± 0.7kJ/molCcbJimenez, Roux, et al., 1987see Jimenez, Roux, et al., 1986; ALS
Deltafsolid116.0 ± 4.6kJ/molCcbBedford, Edmondson, et al., 1962Reanalyzed by Cox and Pilcher, 1970, Original value = 118. ± 4.6 kJ/mol; ALS
Quantity Value Units Method Reference Comment
Deltacsolid  CcbZaheeruddin and Lodhi, 1991uncertain value: -1864.60 kJ/mol; ALS
Deltacsolid-1857.6 ± 0.6kJ/molCcbJimenez, Roux, et al., 1987see Jimenez, Roux, et al., 1986; ALS
Deltacsolid-1868.2 ± 4.6kJ/molCcbBedford, Edmondson, et al., 1962Reanalyzed by Cox and Pilcher, 1970, Original value = -1870.8 ± 4.6 kJ/mol; ALS
Deltacsolid-1859.kJ/molCcbZimmerman and Geisenfelder, 1961ALS

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
81.0298.15Jimenez, Roux, et al., 1987Cp given as 1.19 J/g*K.; DH
87.9300.DeWit, Offringa, et al., 1983T = 300 to 450 K.; DH

Reaction thermochemistry 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
RCD - Robert C. Dunbar

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

C3H3N2- + Hydrogen cation = 1H-Pyrazole

By formula: C3H3N2- + H+ = C3H4N2

Quantity Value Units Method Reference Comment
Deltar1479. ± 10.kJ/molG+TSGianola, Ichino, et al., 2006gas phase; B
Deltar1479. ± 10.kJ/molG+TSTaft, Anvia, et al., 1986gas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Deltar1449. ± 9.6kJ/molN/AGianola, Ichino, et al., 2006gas phase; B
Deltar1449. ± 9.6kJ/molIMRETaft, Anvia, et al., 1986gas phase; value altered from reference due to change in acidity scale; B

Lithium ion (1+) + 1H-Pyrazole = (Lithium ion (1+) bullet 1H-Pyrazole)

By formula: Li+ + C3H4N2 = (Li+ bullet C3H4N2)

Quantity Value Units Method Reference Comment
Deltar187. ± 17.kJ/molCIDTHuang and Rodgers, 2002RCD

Sodium ion (1+) + 1H-Pyrazole = (Sodium ion (1+) bullet 1H-Pyrazole)

By formula: Na+ + C3H4N2 = (Na+ bullet C3H4N2)

Quantity Value Units Method Reference Comment
Deltar128. ± 9.2kJ/molCIDTHuang and Rodgers, 2002RCD

Potassium ion (1+) + 1H-Pyrazole = (Potassium ion (1+) bullet 1H-Pyrazole)

By formula: K+ + C3H4N2 = (K+ bullet C3H4N2)

Quantity Value Units Method Reference Comment
Deltar84. ± 3.kJ/molCIDTHuang and Rodgers, 2002RCD

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Notes

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

Zaheeruddin and Lodhi, 1991
Zaheeruddin, M.; Lodhi, Z.H., Enthalpies of formation of some cyclic compounds, Phys. Chem. (Peshawar Pak.), 1991, 10, 111-118. [all data]

Jimenez, Roux, et al., 1987
Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of N-heterocyclic compounds. I. Enthalpies of combustion, vapour pressures and enthalpies of sublimation, and enthalpies of formation of pyrazole, imidazole, indazole, and benzimidazole, J. Chem. Thermodyn., 1987, 19, 985-992. [all data]

Jimenez, Roux, et al., 1986
Jimenez, P.; Roux, M.V.; Turrion, C.; Gomis, F., Thermochemical properties of some N-heterocyclic compounds, J. Calorim. Anal. Therm. Thermodyn. Chim., 1986, 17, 469-470. [all data]

Bedford, Edmondson, et al., 1962
Bedford, A.F.; Edmondson, P.B.; Mortimer, C.T., Heats of formation and bond energies. Part VI. n-Butyliso-butyraldimine, n-butylisobutylamine, pyrazole, and imidazole, J. Chem. Soc., 1962, 2927-2931. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H., Uber die Mesomerieenergie von Azolen, Z. Electrochem., 1961, 65, 368-371. [all data]

DeWit, Offringa, et al., 1983
DeWit, H.G.M.; Offringa, J.C.A.; De Kruif, C.G.; Van Miltenburg, J.C., Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen and sulfur. III. Molar heat capacities measured by differential scanning calorimetry, Thermochim. Acta, 1983, 65, 43-51. [all data]

Gianola, Ichino, et al., 2006
Gianola, A.J.; Ichino, T.; Kato, S.; Bierbaum, V.M.; Lineberger, W.C., Thermochemical studies of pyrazolide, J. Phys. Chem. A, 2006, 110, 27, 8457-8466, https://doi.org/10.1021/jp057499+ . [all data]

Taft, Anvia, et al., 1986
Taft, R.W.; Anvia, F.; Taagepera, M.; Catalan, J.; Elgueroy, J., Electrostatic proximity effects in the relative basicities of pyrazole, imidazole, pyridazine, and pyrimidine, J. Am. Chem. Soc., 1986, 108, 3237. [all data]

Huang and Rodgers, 2002
Huang, H.; Rodgers, M.T., Sigma versus Pi interactions in alkali metal ion binding to azoles: Threshold collision-induced dissociation and ab initio theory studies, J. Phys. Chem. A, 2002, 106, 16, 4277, https://doi.org/10.1021/jp013630b . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References