Difluoromethane

• Formula: CH₂F₂
• Molecular weight: 52.0234
• IUPAC Standard InChI: InChI=1S/CH2F2/c2-1-3/h1H2 Copy

  
• IUPAC Standard InChIKey: RWRIWBAIICGTTQ-UHFFFAOYSA-N Copy
• CAS Registry Number: 75-10-5
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Freon 32; Methane, difluoro-; Methylene fluoride; Carbon fluoride hydride; Genetron 32; Methylene difluoride; CH2F2; R 32; HFC 32; R 32 (refrigerant)
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Fluid Properties
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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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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:
BS - Robert L. Brown and Stephen E. Stein
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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Enthalpy of fusion

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

Gas Chromatography

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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

Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), Gas Chromatography, 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]

Neugebauer and Margrave, 1958
Neugebauer, C.A.; Margrave, J.L., The heats of formation of CHF₃ and CH₂F₂, J. Phys. Chem., 1958, 62, 1043-1048. [all data]

PCR Inc., 1990
PCR Inc., Research Chemicals Catalog 1990-1991, PCR Inc., Gainesville, FL, 1990, 1. [all data]

Filatov, Makarov, et al., 1968
Filatov, A.S.; Makarov, S.P.; Yakubovich, A.Ya., Halogenation of 1,1,1-Trifluoroazomethane, Zh. Obshch. Khim., 1968, 38, 33. [all data]

Croll and Scott, 1964
Croll, I.M.; Scott, R.L., Fluorocarbon Solutions at Low Termperatures IV. The Liquid Mixtures CH4 + CClF3, CH2F2 + CClF3, CHF3 + CClF3, CF4 + CClF3, C2H6 + CClF3, C2H6 + CF4, and CHF3 + CF4, J. Phys. Chem., 1964, 68, 3853. [all data]

Henne, Renoll, et al., 1939
Henne, A.L.; Renoll, M.W.; Leicester, H.M., J. Am. Chem. Soc., 1939, 61, 938. [all data]

Shi, Zhu, et al., 1998
Shi, L.; Zhu, M.; Han, L.; Duan, Y.; Sun, L.; Fu, Y.-D., Thermophysical Properties of Difluoromethane (HFC-32), Science in China, Ser. E, 1998, 41, 435-42. [all data]

Fu, Han, et al., 1995
Fu, Y.D.; Han, L.-Z.; Zhu, M.-S., PVT properties, vapor pressures and critical parameters of HFC-32, Fluid Phase Equilib., 1995, 111, 273-86. [all data]

Higashi, 1994
Higashi, Y., Critical parameters for HFC134a, HFC32 and HFC125, Int. J. Refrig., 1994, 17, 524-531. [all data]

Sato, Sato, et al., 1994
Sato, T.; Sato, H.; Watanabe, K., PVT Property Measurements for Difluoromethane, J. Chem. Eng. Data, 1994, 39, 851-4. [all data]

Kanungo, Oi, et al., 1987
Kanungo, Arundhati.; Oi, Takao.; Popowicz, Anthony.; Ishida, Takanobu., Vapor pressure isotope effects in liquid methylene difluoride, J. Phys. Chem., 1987, 91, 15, 4198-4203, https://doi.org/10.1021/j100299a049 . [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]

Malbrunot, Meunier, et al., 1968
Malbrunot, P.F.; Meunier, P.A.; Scatena, Georges M.; Mears, Whitney H.; Murphy, Kevin Paul.; Sinka, Joseph V., Pressure-volume-temperature behavior of difluoromethane, J. Chem. Eng. Data, 1968, 13, 1, 16-21, https://doi.org/10.1021/je60036a006 . [all data]

L«65533»ddecke and Magee, 1996
L«65533»ddecke, T.O.; Magee, J.W., Molar heat capacity at constant volume of difluoromethane (R32) and pentafluoroethane (R125) from the triple-point temperature to 345 K at pressures to 35 MPa, Int J Thermophys, 1996, 17, 4, 823-849, https://doi.org/10.1007/BF01439192 . [all data]

Zenkevich, 2005
Zenkevich, I.G., Experimentally measured retention indices., 2005. [all data]

Zenkevich and Rodin, 2004
Zenkevich, I.G.; Rodin, A.A., Gas chromatographic identification of some volatile toxic fluorine containing compounds by precalculated retention indices, J. Ecol. Chem. (Rus.), 2004, 13, 1, 22-28. [all data]

Notes

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

• Symbols used in this document:
  

  Pc	Critical pressure
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  Tboil	Boiling point
  Tc	Critical temperature
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔvapH	Enthalpy of vaporization
  ρc	Critical density

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