1H-1,2,4-Triazole
- Formula: C2H3N3
- Molecular weight: 69.0653
- IUPAC Standard InChI: InChI=1S/C2H3N3/c1-3-2-5-4-1/h1-2H,(H,3,4,5)
- IUPAC Standard InChIKey: NSPMIYGKQJPBQR-UHFFFAOYSA-N
- CAS Registry Number: 288-88-0
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Species with the same structure:
- Other names: s-Triazole; 1,2,4-Triazole; 1,2,4-1H-Triazole; CGA-71019; Pyrrodiazole
- Information on this page:
- Other data available:
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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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | 192.7 ± 0.8 | kJ/mol | Ccb | Jimenez, Roux, et al., 1989 | ALS |
| ΔfH°gas | 193.7 ± 1.9 | kJ/mol | Ccb | Faour and Akasheh, 1985 | ALS |
| ΔfH°gas | 188.5 | kJ/mol | N/A | Masalitinova, Oleinikova, et al., 1984 | Value computed using ΔfHsolid° value of 107.9±0.5 kj/mol from Masalitinova, Oleinikova, et al., 1984 and ΔsubH° value of 80.6 kj/mol from Jimenez, Roux, et al., 1989.; DRB |
| ΔfH°gas | 189.8 | kJ/mol | N/A | Aleksandrov, Osipova, et al., 1982 | Value computed using ΔfHsolid° value of 109.2±0.9 kj/mol from Aleksandrov, Osipova, et al., 1982 and ΔsubH° value of 80.6 kj/mol from Jimenez, Roux, et al., 1989.; DRB |
Condensed phase thermochemistry data
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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 |
|---|---|---|---|---|---|
| ΔfH°solid | 108.7 ± 0.4 | kJ/mol | Ccb | Jimenez, Roux, et al., 1989 | ALS |
| ΔfH°solid | 113.1 ± 1.4 | kJ/mol | Ccb | Faour and Akasheh, 1985 | ALS |
| ΔfH°solid | 107.89 ± 0.46 | kJ/mol | Ccb | Masalitinova, Oleinikova, et al., 1984 | ALS |
| ΔfH°solid | 109.22 ± 0.94 | kJ/mol | Ccb | Aleksandrov, Osipova, et al., 1982 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -1324.4 ± 0.3 | kJ/mol | Ccb | Jimenez, Roux, et al., 1989 | ALS |
| ΔcH°solid | -1328.9 ± 1.2 | kJ/mol | Ccb | Faour and Akasheh, 1985 | ALS |
| ΔcH°solid | -1323.66 ± 0.37 | kJ/mol | Ccb | Masalitinova, Oleinikova, et al., 1984 | ALS |
| ΔcH°solid | -1324.99 ± 0.90 | kJ/mol | Ccb | Aleksandrov, Osipova, et al., 1982 | ALS |
| ΔcH°solid | -1325. | kJ/mol | Ccb | Zimmerman and Geisenfelder, 1961 | ALS |
Constant pressure heat capacity of solid
| Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 78.7 | 298.15 | Jimenez, Roux, et al., 1989 | DH |
Reaction thermochemistry data
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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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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
C2H2N3- + =
By formula: C2H2N3- + H+ = C2H3N3
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1440. ± 8.8 | kJ/mol | G+TS | Taft, 1991 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1410. ± 8.4 | kJ/mol | IMRE | Taft, 1991 | gas phase; B |
+
= (
•
)
By formula: Na+ + C2H3N3 = (Na+ • C2H3N3)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 124. ± 5.0 | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 0.0 | 0. | CIDT | Rodgers and Armentrout, 2000 | RCD |
+
=
+
By formula: C4H5N3O + H2O = C2H3N3 + C2H4O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -30.5 ± 0.3 | kJ/mol | Cm | Wadso, 1960 | solid phase; Heat of hydrolysis; ALS |
+
=
+
By formula: C4H11N + C4H5N3O = C6H13NO + C2H3N3
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -85.8 ± 0.3 | kJ/mol | Cm | Wadso, 1962 | solid phase; ALS |
=
By formula: C2H3N3 = C2H3N3
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 12. | kJ/mol | Eqk | Mauret, Fayet, et al., 1973 | liquid phase; solvent: Benzene; ALS |
+
=
+
By formula: C4H5N3O + C6H7N = C8H9NO + C2H3N3
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -72.3 ± 0.3 | kJ/mol | Cm | Wadso, 1962 | solid phase; ALS |
+
= (
•
)
By formula: Li+ + C2H3N3 = (Li+ • C2H3N3)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 191. ± 7.9 | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
+
= (
•
)
By formula: K+ + C2H3N3 = (K+ • C2H3N3)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 87.0 ± 5.0 | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | RCD |
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.
Jimenez, Roux, et al., 1989
Jimenez, P.; Roux, M.V.; Turrion, C.,
Thermochemical properties of N-heterocyclic compounds II. Enthalpies of combustion, vapour pressures, enthalpies of sublimation, and enthalpies of formation of 1,2,4-triazole and benzotriazole,
J. Chem. Thermodyn., 1989, 21, 759-764. [all data]
Faour and Akasheh, 1985
Faour, M.; Akasheh, T.S.,
Heat of combustion of some N-heterocycle compounds. Part 1,
J. Chem. Soc. Perkin Trans. 2, 1985, 811-713. [all data]
Masalitinova, Oleinikova, et al., 1984
Masalitinova, T.N.; Oleinikova, T.P.; Polyakova, L.P.,
Thermochemical study of 1,2,4-triazole as a reference substnace for the calorimetry of combustion of organonitrogen compounds,
Ref. Zh., Khim.; Abstr. No. 7B3028, 1984, 0. [all data]
Aleksandrov, Osipova, et al., 1982
Aleksandrov, Yu.I.; Osipova, T.R.; Yuhkevich, V.F.,
Study of 1,2,4-triazole as a standard sample in the calorimetry of thoroughly nitrided organic compounds,
Termodin. Organ. Soedin., 1982, 42-45. [all data]
Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H.,
Uber die Mesomerieenergie von Azolen,
Z. Electrochem., 1961, 65, 368-371. [all data]
Taft, 1991
Taft, R.W.,
, personal communication, Aug, 1991. [all data]
Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B.,
Noncovalent Metal-Ligand Bond Energies as Studied by Threshold Collision-Induced Dissociation,
Mass Spectrom. Rev., 2000, 19, 4, 215, https://doi.org/10.1002/1098-2787(200007)19:4<215::AID-MAS2>3.0.CO;2-X
. [all data]
Wadso, 1960
Wadso, I.,
Heats of hydrolysis of N-acetylated imidazole, 1,2,4-triazole and tetrazole,
Acta Chem. Scand., 1960, 14, 903-908. [all data]
Wadso, 1962
Wadso, I.,
Heats of aminolysis and hydrolysis of some N-acetyl compounds and of acetic anhydride,
Acta Chem. Scand., 1962, 16, 471-478. [all data]
Mauret, Fayet, et al., 1973
Mauret, P.; Fayet, J.P.; Fabre, M.; Elguero, J.; Pardo, M.d.C.,
Tautomerism study of υ-triazole from dipolar moment measurements,
J. Chim. Phys. Phys.-Chim. Biol., 1973, 70, 1483-1485. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid T Temperature ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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