Difluoromethane

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Difluoromethane
Stereo skeletal formula of difluoromethane with all explicit hydrogens added
Spacefill model of difluoromethane
Names
Systematic IUPAC name
Difluoromethane[1]
Other names
Carbon fluoride hydride

Methylene difluoride
Methylene fluoride

Freon-32
Identifiers
75-10-5 YesY
Abbreviations HFC-32

R-32
FC-32

1730795
ChEBI CHEBI:47855 YesY
ChEMBL ChEMBL115186 YesY
ChemSpider 6105 YesY
EC number 200-839-4
259463
Jmol-3D images Image
MeSH Difluoromethane
PubChem 6345
RTECS number PA8537500
UN number 3252
Properties
CH2F2
Molar mass 52.02 g·mol−1
Appearance Colorless gas
Density 1.1 g cm−3
Melting point −136 °C (−213 °F; 137 K)
Boiling point −52 °C (−62 °F; 221 K)
log P -0.611
Vapor pressure 1518.92 kPa (at 21.1 °C)
Hazards
Safety data sheet See: data page
MSDS at Oxford University
EU classification Highly Flammable F
R-phrases R11
S-phrases S9, S16, S33
NFPA 704
Flammability code 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g., propane Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g., calcium Special hazards (white): no codeNFPA 704 four-colored diamond
648 °C (1,198 °F; 921 K)
Supplementary data page
Refractive index (n),
Dielectric constantr), etc.
Thermodynamic
data
Phase behaviour
solid–liquid–gas
UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Difluoromethane, also called HFC-32 or R-32, is an organic compound of the dihalogenoalkane variety. It is based on methane, except that two of the four hydrogen atoms have been replaced by fluorine atoms. Hence the formula is CH2F2 instead of CH4 for normal methane.

Uses[edit]

Difluoromethane is a refrigerant that has zero ozone depletion potential. Difluoromethane in a zeotropic (50%/50%) m/m mixture with pentafluoroethane (R-125) is known as R-410A, a common replacement for various chlorofluorocarbons (aka Freon) in new refrigerant systems, especially for air-conditioning. The zeotropic mix of difluoromethane with pentafluoroethane (R-125) and tetrafluoroethane (R-134a) is known as R-407A through R-407E depending on the composition. Likewise the azeotropic (48.2%/51.8% m/m) mixture with chlorotrifluoromethane (R13). As a refrigerant difluoromethane is classified as A2L - slightly flammable [2009 ASHRAE Handbook]. Although it has zero ozone depletion potential, it has global warming potential 675 times that of carbon dioxide, based on a 100-year time frame [May 2010 TEAP XXI/9 Task Force Report].

References[edit]

  1. ^ "Difluoromethane - Compound Summary". The PubChem Project. USA: National Center of Biotechnological Information. 

External links[edit]