Difluoromethane
- Formula: CH2F2
- Molecular weight: 52.0234
- IUPAC Standard InChIKey: RWRIWBAIICGTTQ-UHFFFAOYSA-N
- 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
The 3d structure may be viewed using Java or Javascript. - 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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Phase change data
Go To: Top, 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:
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 221.4 | K | N/A | PCR Inc., 1990 | BS |
Tboil | 221. | K | N/A | Filatov, Makarov, et al., 1968 | Uncertainty assigned by TRC = 2. K; TRC |
Tboil | 221.6 | K | N/A | Croll and Scott, 1964 | Uncertainty assigned by TRC = 0.3 K; TRC |
Tboil | 221.6 | K | N/A | Henne, Renoll, et al., 1939 | Uncertainty assigned by TRC = 1. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 351.3 ± 0.1 | K | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 57.85 | bar | N/A | Shi, Zhu, et al., 1998 | Uncertainty assigned by TRC = 0.03 bar; by extrapolation of vapor pressure to Tc; TRC |
Pc | 57.85 | bar | N/A | Fu, Han, et al., 1995 | Uncertainty assigned by TRC = 0.04 bar; TRC |
Pc | 57.85 | bar | N/A | Higashi, 1994 | Uncertainty assigned by TRC = 0.09 bar; TRC |
Pc | 57.840 | bar | N/A | Sato, Sato, et al., 1994 | Uncertainty assigned by TRC = 0.025 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 8.2 ± 0.1 | mol/l | AVG | N/A | Average of 7 values; Individual data points |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
20.6 | 230. | N/A | Kanungo, Oi, et al., 1987 | Based on data from 149. to 245. K.; AC |
19.9 | 271. | A | Stephenson and Malanowski, 1987 | Based on data from 256. to 321. K.; AC |
21.2 | 207. | A | Stephenson and Malanowski, 1987 | Based on data from 191. to 222. K.; AC |
20.3 | 243. | A | Stephenson and Malanowski, 1987 | Based on data from 191. to 258. K.; AC |
20.3 | 331. | A | Stephenson and Malanowski, 1987 | Based on data from 316. to 351. K.; AC |
21.2 | 206. | N/A | Malbrunot, Meunier, et al., 1968 | Based on data from 191. to 221. K.; AC |
20.6 | 227. | N/A | Malbrunot, Meunier, et al., 1968 | Based on data from 191. to 242. K.; AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
191.19 to 241.33 | 4.26224 | 821.092 | -28.554 | Malbrunot, Meunier, et al., 1968 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
4.36 | 136.4 | L«65533»ddecke and Magee, 1996 | AC |
References
Go To: Top, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Notes
Go To: Top, Phase change data, References
- Symbols used in this document:
Pc Critical pressure Tboil Boiling point Tc Critical temperature 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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