Difluoromethane
- Formula: CH2F2
- Molecular weight: 52.0234
- IUPAC Standard InChI: InChI=1S/CH2F2/c2-1-3/h1H2
- 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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Reaction thermochemistry 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
MS - José A. Martinho Simões
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
CHF2- + =
By formula: CHF2- + H+ = CH2F2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 389.0 ± 3.5 | kcal/mol | CIDT | Graul and Squires, 1990 | gas phase; G2 calculations( Lee, Dyke, et al., 1998) predict ΔHacid = 399 kcal/mol; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 381.2 ± 3.6 | kcal/mol | H-TS | Graul and Squires, 1990 | gas phase; G2 calculations( Lee, Dyke, et al., 1998) predict ΔHacid = 399 kcal/mol; B |
| ΔrG° | 379.0 ± 6.0 | kcal/mol | IMRB | Sullivan, 1977 | gas phase; B |
+
= (
•
)
By formula: Li+ + CH2F2 = (Li+ • CH2F2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 26.5 | kcal/mol | ICR | Staley and Beauchamp, 1975 | gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 interpolated; M |
C5O5W (g) + (g) = C6H2F2O5W (g)
By formula: C5O5W (g) + CH2F2 (g) = C6H2F2O5W (g)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | >-5.00 | kcal/mol | EqG | Brown, Ishikawa, et al., 1990 | Temperature range: ca. 300-350 K; MS |
+
=
+
By formula: CH2F2 + Br2 = HBr + CHBrF2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -9.54 ± 0.07 | kcal/mol | Eqk | Okafo and Whittle, 1974 | gas phase; ALS |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Graul and Squires, 1990
Graul, S.T.; Squires, R.R.,
Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions,
J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007
. [all data]
Lee, Dyke, et al., 1998
Lee, E.P.F.; Dyke, J.M.; Mayhew, C.A.,
Study of the OH-+CH2F2 reaction by selected ion flow tube experiments and ab initio calculations,
J. Phys. Chem. A, 1998, 102, 43, 8349-8354, https://doi.org/10.1021/jp982224y
. [all data]
Sullivan, 1977
Sullivan, S.A.,
Thesis, Cal. Inst. Tech. thesis,, 1977. [all data]
Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L.,
Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases,
J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050
. [all data]
Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P.,
Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n,
J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013
. [all data]
Brown, Ishikawa, et al., 1990
Brown, C.E.; Ishikawa, Y.; Hackett, P.A.; Rayner, D.M.,
J. Am. Chem. Soc., 1990, 112, 2530. [all data]
Okafo and Whittle, 1974
Okafo, E.N.; Whittle, E.,
Bond dissociation energies from equilibrium studies. Part 5.-The equilibria Br2 + CH2F2 = HBr + CHF2Br and Br2 + CH3F = HBr + CH2FBr. Determination of D(CHF2-Br) and ΔH°f (CHF2Br,g),
Trans. Faraday Soc., 1974, 17, 1366-1375. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
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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