Hydrazine

• Formula: H₄N₂
• Molecular weight: 32.0452
• IUPAC Standard InChI: InChI=1S/H4N2/c1-2/h1-2H2 Copy

  
• IUPAC Standard InChIKey: OAKJQQAXSVQMHS-UHFFFAOYSA-N Copy
• CAS Registry Number: 302-01-2
• 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.
• Other names: Levoxine; N2H4; Diamine; Hydrazyna; Rcra waste number U133; Hydrazine, anhydrous; Hydrazine base; Nitrogen hydride, (N2H4); Oxytreat 35
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Gas 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

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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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.

Liquid Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Phase change 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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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 by: 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

 + 0.5 =  +  + 0.5

By formula: C₄H₄BrNO₂ + 0.5H₄N₂ = HBr + C₄H₅NO₂ + 0.5N₂

 + 0.5 =  +  + 0.5

By formula: C₄H₄ClNO₂ + 0.5H₄N₂ = C₄H₅NO₂ + HCl + 0.5N₂

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
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

View reactions leading to H₄N₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

Mass spectrum (electron ionization)

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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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Willis, Lossing, et al., 1976
Willis, C.; Lossing, F.P.; Back, R.A., The heat of formation of N₂H₂ and the proton affinity of N₂, Can. J. Chem., 1976, 54, 1-3. [all data]

Cole and Gilbert, 1951
Cole, L.G.; Gilbert, E.C., The heats of combustion of some nitrogen compounds and the apparent energy of the N-N bond, J. Am. Chem. Soc., 1951, 73, 5423-5427. [all data]

Tipton, Stone, et al., 1989
Tipton, T.; Stone, D.A.; KuBulat, K.; Person, W.B., Experimental and theoretical studies of the infrared spectra of hydrazines: N2H4, N2H3D, N2H2D2, N2HD3, and N2D4, J. Phys. Chem., 1989, 93, 2917. [all data]

Ferren, Miller, et al., 1957
Ferren, R.A.; Miller, J.G.; Day, A.R., J. Am. Chem. Soc., 1957, 79, 70. [all data]

Burtle, 1952
Burtle, J.G., Vapor Pressure-Composition Measurement son Aqueous Hydrazine Solutions, Ind. Eng. Chem., 1952, 44, 1675. [all data]

McMillan, 1967
McMillan, J.A., Hydrazine-1,1-Dimethylhydrazine Solid-Liquid Phase Diagram, J. Chem. Eng. Data, 1967, 12, 39. [all data]

Lempe, Neuhaeuser, et al., 1966
Lempe, D.; Neuhaeuser, S.; Maeder, H.J.; Bittrich, H.-J., Equilibriums in Ternary Liquid-Liquid Systems; Triethylamine + Water and Monoethylamine, Diethylamine, and Hydrazine, Wiss. Z. Tech. Hochsch. Chem. "Carl Schorlemmer" Leuna-Me- rseburg, 1966, 8, 158. [all data]

Bruhl, 1897
Bruhl, J.W., Spectrochemistry of nitrogen containing compounds V, Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1897, 22, 373. [all data]

Scott, Oliver, et al., 1949
Scott, D.W.; Oliver, G.D.; Gross, M.E.; Hubbard, W.N.; Huffman, H.M., Hydrazine: Heat Capacity, Heats of Fusion and Vaporization, Vapor Pressure, Entropy and Thermodynamic Functions, J. Am. Chem. Soc., 1949, 71, 2293-7. [all data]

Scott, Oliver, et al., 1949, 2
Scott, D.W.; Oliver, G.D.; Gross, Margaret E.; Hubbard, W.N.; Huffman, Hugh M., Hydrazine: Heat Capacity, Heats of Fusion and Vaporization, Vapor Pressure, Entropy and Thermodynamic Functions, J. Am. Chem. Soc., 1949, 71, 7, 2293-2297, https://doi.org/10.1021/ja01175a007 . [all data]

Howard and Skinner, 1966
Howard, P.B.; Skinner, H.A., Thermochemistry of some reactions of aqueous hydrazine with halogens, hydrogen halides and N-halogenosuccinimides, J. Chem. Soc. A, 1966, 1536-1540. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Mautner(Meot-Ner), Nelsen, et al., 1984
Mautner(Meot-Ner), M.; Nelsen, S.F.; Willi, M.R.; Frigo, T.B., Special effects of an unusually large neutral to radical cation geometry change. Adiabatic ionization energies and proton affinities of alkylhydrazines, J. Am. Chem. Soc., 1984, 106, 7384. [all data]

Wiberg, Fischer, et al., 1979
Wiberg, N.; Fischer, G.; Bachhuber, H., Diazen und andere Distickstoffhydride: Bildungswarmen, Dissoziationsenergien, Auftrittspotentiale, Protonenaffinitaten, Z. Naturforsch. B:, 1979, 34, 1385. [all data]

Bodor, Dewar, et al., 1970
Bodor, N.; Dewar, M.J.S.; Jennings, W.B.; Worley, S.D., Photoelectron spectra of molecules-IV.Ionization potentials and heats of formation of some hydrazines and amines, Tetrahedron, 1970, 26, 4109. [all data]

Melton, 1966
Melton, C.E., Study by mass spectrometry of the decomposition of ammonia by ionizing radiation in a wide-range radiolysis source, J. Chem. Phys., 1966, 45, 4414. [all data]

Akopyan and Vilesov, 1963
Akopyan, M.E.; Vilesov, F.I., Decay of the molecular ions formed in photoionization of hydrazine and some of its alkyl derivatives, Kinetika i Kataliz, 1963, 4, 39, In original 32. [all data]

Akopyan, Vilesov, et al., 1963
Akopyan, M.E.; Vilesov, F.I.; Terenin, A.N., Mass spectrometric investigation of photoionization of molecules and dissociation of excited molecular ions, Izv. Akad. Nauk SSSR, Ser. Fiz., 1963, 27, 1083, In original 1054. [all data]

Dibeler, Franklin, et al., 1959
Dibeler, V.H.; Franklin, J.L.; Reese, R.M., Electron impact studies of hydrazine and the methyl-substituted hydrazines, J. Am. Chem. Soc., 1959, 81, 68. [all data]

Vilesov and Terenin, 1957
Vilesov, F.I.; Terenin, A.N., The photoionization of the vapors of certain organic compounds, Dokl. Akad. Nauk SSSR, 1957, 115, 744, In original 539. [all data]

Vovna, Vilesov, et al., 1975
Vovna, V.I.; Vilesov, F.I.; Lopatin, S.N., Photoelectron spectra of hydrazine and some alkyl derivatives, Opt. Spectrosc., 1975, 38, 143. [all data]

Rademacher, 1975
Rademacher, P., Acyclische Hydrazine, Chem. Ber., 1975, 108, 1548. [all data]

Nelsen and Buschek, 1974
Nelsen, S.F.; Buschek, J.M., Photoelectron spectra of hydrazines. III. Evidence for similar lone pair-lone pair dihedral angles for acyclic hydrazines, J. Am. Chem. Soc., 1974, 96, 2392. [all data]

Osafune, Katsumata, et al., 1973
Osafune, K.; Katsumata, S.; Kimura, K., Photoelectron spectroscopic study of hydrazine, Chem. Phys. Lett., 1973, 19, 369. [all data]

Barz and Fritz, 1972
Barz, P.; Fritz, H.P., Untersuchungen an biochemish ligandensystemen, V. Komplexchemische und physikalisch-chemische untersuchungen am 1,2-dimethylhydrazin, Z. Naturforsch. B:, 1972, 27, 1131. [all data]

Foner and Hudson, 1958
Foner, S.N.; Hudson, R.L., Mass spectrometric detection of triazene and tetrazene and studies of the free radicals NH₂, and N₂H₃, J. Chem. Phys., 1958, 29, 442. [all data]

Foner and Hudson, 1978
Foner, S.N.; Hudson, R.L., On the heat of formation of diimide, J. Chem. Phys., 1978, 68, 3162. [all data]

Foner and Hudson, 1958, 2
Foner, S.N.; Hudson, R.L., Diimide-identification and study by mass spectrometry, J. Chem. Phys., 1958, 28, 719. [all data]

Fisher and Heath, 1965
Fisher, I.P.; Heath, G.A., Dissociation energy of the N-H bond in hydrazine, Nature, 1965, 208, 1199. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  S°liquid,1 bar	Entropy of liquid at standard conditions (1 bar)
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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