- Formula: C3H4N2
- Molecular weight: 68.0773
- IUPAC Standard InChI:
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- IUPAC Standard InChIKey: WTKZEGDFNFYCGP-UHFFFAOYSA-N
- CAS Registry Number: 288-13-1
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
- Other names: Pyrazole; 1,2-Diazole
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Reaction thermochemistry data
Go To: Top, References, Notes
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.
C3H3N2- + =
By formula: C3H3N2- + H+ = C3H4N2
|rH°||1479. ± 10.||kJ/mol||G+TS||Gianola, Ichino, et al., 2006||gas phase; B|
|rH°||1479. ± 10.||kJ/mol||G+TS||Taft, Anvia, et al., 1986||gas phase; value altered from reference due to change in acidity scale; B|
|rG°||1449. ± 9.6||kJ/mol||N/A||Gianola, Ichino, et al., 2006||gas phase; B|
|rG°||1449. ± 9.6||kJ/mol||IMRE||Taft, Anvia, et al., 1986||gas phase; value altered from reference due to change in acidity scale; B|
+ = ( )
By formula: Li+ + C3H4N2 = (Li+ C3H4N2)
|rH°||187. ± 17.||kJ/mol||CIDT||Huang and Rodgers, 2002||RCD|
+ = ( )
By formula: Na+ + C3H4N2 = (Na+ C3H4N2)
|rH°||128. ± 9.2||kJ/mol||CIDT||Huang and Rodgers, 2002||RCD|
+ = ( )
By formula: K+ + C3H4N2 = (K+ C3H4N2)
|rH°||84. ± 3.||kJ/mol||CIDT||Huang and Rodgers, 2002||RCD|
Go To: Top, Reaction thermochemistry data, Notes
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]
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
rG° Free energy of reaction at standard conditions rH° Enthalpy of reaction at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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