Hydrazine, 1,2-dimethyl-

• Formula: C₂H₈N₂
• Molecular weight: 60.0983
• IUPAC Standard InChI: InChI=1S/C2H8N2/c1-3-4-2/h3-4H,1-2H3 Copy

  
• IUPAC Standard InChIKey: DIIIISSCIXVANO-UHFFFAOYSA-N Copy
• CAS Registry Number: 540-73-8
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: s-Dimethylhydrazine; DMH; Hydrazomethane; N,N'-Dimethylhydrazine; SDMH; 1,2-Dimethylhydrazine; (CH3NH)2; 1,2-Dimethylhydrazin; sym-Dimethylhydrazine; Dimethylhydrazine, symmetrical; Rcra waste number U099; Symetryczna dwumetylohydrazyna; UN 2382
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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.

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

Constant pressure heat capacity of liquid

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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Antoine Equation Parameters

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

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Enthalpy of fusion

Entropy of fusion

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 compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LL - Sharon G. Lias and Joel F. Liebman

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, Condensed phase thermochemistry data, Phase change 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.

Aston, Rock, et al., 1952
Aston, J.G.; Rock, E.J.; Isserow, S., The heats of combustion of the methyl substituted hydrazines and some observations on the burning of volatile liquids, J. Am. Chem. Soc., 1952, 74, 2484-24. [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]

Aston, Janz, et al., 1951
Aston, J.G.; Janz, G.J.; Russell, K.E., The heat capacity, heats of fusion and vaporization, vapor pressures and entropy of symmetrical dimethylhydrazine, J. Am. Chem. Soc., 1951, 73, 1943-1945. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Aston, Janz, et al., 1951, 2
Aston, J.G.; Janz, G.J.; Russell, K.E., The Heat Capacity, Heats of Fusion and Vaporization, Vapor Pressures and Entropy of Symmetrtical Dimethylhydrazine, J. Am. Chem. Soc., 1951, 73, 1943. [all data]

Aston, Janz, et al., 1951, 3
Aston, J.G.; Janz, G.J.; Russell, K.E., The heat capacity, heats of fusion and vaporization, vapor pressures and entropy of symmetrical dimethylhydrazine, J. Am. Chem. Soc., 1951, 73, 1943-19. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [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]

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]

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]

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

Kimura and Osafune, 1975
Kimura, K.; Osafune, K., Photoelectron spectroscopic study of skew compounds. III. N,N'-dimethylhydrazine, dimethyl peroxide, and dimethyl disulfide, Bull. Chem. Soc. Jpn., 1975, 48, 2421. [all data]

Nelsen and Buschek, 1974
Nelsen, S.F.; Buschek, J.M., Photoelectron spectra of hydrazines. IV. Empirical estimation of lone pair-lone pair dihedral angles and prediction of lone pair ionization potentials for some cyclic and bicyclic hydrazines, J. Am. Chem. Soc., 1974, 96, 6982. [all data]

Nelsen and Buschek, 1974, 2
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]

Burgers, Drewello, et al., 1989
Burgers, P.C.; Drewello, T.; Schwarz, H.; Terlouw, J.K., CH₅N₂ hydrazyl radicals, cations and dication radicals studied by mass spectrometry. Is the N-protonated formaldehyde hydrazon cation ⁺CH₂-NH-NH₂ a bridged species?, Int. J. Mass Spectrom. Ion Processes, 1989, 95, 157. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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