Difluoromethane

Difluoromethane
Systematic name Difluoromethane[1]
Other names Carbon fluoride hydride Methylene difluoride Methylene fluoride Freon-32
Identifiers
Abbreviations	HFC-32 R-32 FC-32
CAS number	75-10-5 Y
PubChem	6345
ChemSpider	6105 Y
EC number	200-839-4
UN number	3252
MeSH	Difluoromethane
ChEBI	CHEBI:47855 Y
ChEMBL	CHEMBL115186 Y
RTECS number	PA8537500
Beilstein Reference	1730795
Gmelin Reference	259463
Jmol-3D images	Image 1
SMILES FCF
InChI InChI=1S/CH2F2/c2-1-3/h1H2 Y Key: RWRIWBAIICGTTQ-UHFFFAOYSA-N Y InChI=1/CH2F2/c2-1-3/h1H2 Key: RWRIWBAIICGTTQ-UHFFFAOYAC
Properties
Molecular formula	CH2F2
Molar mass	52.02 g mol−1
Exact mass	52.012456474 g mol-1
Appearance	Colorless gas
Density	1.1 g cm-3
Melting point	−136 °C, 137 K, -213 °F
Boiling point	−52 °C, 221 K, -62 °F
log P	-0.611
Vapor pressure	1518.92 kPa (at 21.1 °C)
Hazards
MSDS	MSDS at Oxford University
EU classification	F
R-phrases	R11
S-phrases	S9, S16, S33
NFPA 704	4 1 1
Autoignition temperature	648 °C
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
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 It is based on methane, except that two of the four hydrogen atoms have been replaced by fluorine atoms.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.

Physical properties

Property	Value
Critical pressure (pc)	5.83 MPa
Critical temperature (Tc)	78.45 °C (351 K)
Compressibility factor (Z)	0.9863
Heat capacity at constant pressure (Cp) at 21 °C (70 °F)	0.043 kJ·mol−1·K−1
Heat capacity at constant volume (CV) at 21 °C (70 °F)	0.034 kJ·mol−1·K−1
Heat capacity ratio (κ)	1.253

Uses

Difluoromethane is a refrigerant that has zero ozone depletion potential. Difluoromethane in a zeotropic (50%/50%) w/w 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% w/w) 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

1. ^ "Difluoromethane - Compound Summary". The PubChem Project. USA: National Center of Biotechnological Information. http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6345&loc=ec_rcs. 

External links

• Flammability Measurements of Difluoromethane in Air at 100°C
• Difluoromethane at Gas Encyclopaedia
• IR absorption spectra

This article about an organic halide is a stub. You can help Wikipedia by expanding it.v · Categories: Organofluorides Halomethanes Refrigerants Organohalide stubs Wikimedia Foundation. 2010. Игры ⚽ Нужна курсовая? Museum Domain Management Association Franciszek Jamroż Look at other dictionaries: Difluorométhane — Général Nom IUPAC …   Wikipédia en Français difluoromethane — noun A dihalogenoalkane in which two of the four hydrogen atoms of methane are replaced by fluorine, used as a refrigerant …   Wiktionary 75-10-5 — Difluorométhane Difluorométhane Général …   Wikipédia en Français CH2F2 — Difluorométhane Difluorométhane Général …   Wikipédia en Français HFC-32 — Difluorométhane Difluorométhane Général …   Wikipédia en Français R32 — Difluorométhane Difluorométhane Général …   Wikipédia en Français R 32 — Difluorométhane Difluorométhane Général …   Wikipédia en Français Liste des numéros ONU — Cette liste répertorie les numéros ONU utilisés dans le transport de matières dangereuses. Sommaire 1 De 0 à 100 2 De 100 à 200 3 De 200 à 300 4 De 300 à 400 …   Wikipédia en Français Halomethane — compounds are derivatives of methane (CH4) with one or more of the hydrogen atoms replaced with halogen atoms (F, Cl, Br, or I). Halomethanes are both naturally occurring, especially in marine environments, and man made, most notably as… …   Wikipedia R32 — may refer to: * R32 (airship), a British airship that first flew in 1919 * R32 (Eastern Cape), a regional route in South Africa * R32 (New York City Subway car), a New York City Subway car design * R32 road (Senegal) * , a risk phrase * BMW R32,… …   Wikipedia 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”