Dichlorodifluoromethane

Dichlorodifluoromethane

Names
Preferred IUPAC name Dichloro(difluoro)methane
Other names Dichlorodifluoromethane Carbon dichloride difluoride Dichloro-difluoro-methane Difluorodichloromethane Freon 12 R-12 CFC-12 P-12 Propellant 12 Halon 122 Arcton 6 Arcton 12 E940 Fluorocarbon 12 Genetron 12 Refrigerant 12
Identifiers
CAS Number	75-71-8 Y
3D model (Jmol)	Interactive image
ChEMBL	ChEMBL2106634 N
ChemSpider	6151 Y
ECHA InfoCard	100.000.813
EC Number	200-893-9
E number	E940 (glazing agents, ...)
KEGG	D03789 Y
PubChem	6391
RTECS number	PA8200000
UNII	OFM06SG1KO Y
UN number	1028
InChI InChI=1S/CCl2F2/c2-1(3,4)5 Y Key: PXBRQCKWGAHEHS-UHFFFAOYSA-N Y InChI=1/CCl2F2/c2-1(3,4)5 Key: PXBRQCKWGAHEHS-UHFFFAOYAX
SMILES ClC(Cl)(F)F
Properties
Chemical formula	CCl2F2
Molar mass	120.91 g·mol−1
Appearance	Colorless gas with ether-like odor
Odor	ether-like at very high concentrations
Density	1.486 g/cm3 (−29.8 °C (−21.6 °F))
Melting point	−157.7 °C (−251.9 °F; 115.5 K)
Boiling point	−29.8 °C (−21.6 °F; 243.3 K)
Solubility in water	0.286 g/l at 20 °C (68 °F)
Solubility in alcohol, ether, benzene, acetic acid	Soluble
log P	2.16
Vapor pressure	568 kPa (20 °C (68 °F))
Henry's law constant (kH)	0.0025 mol kg−1 bar−1
Magnetic susceptibility (χ)	-52.2·10−6 cm3/mol
Hazards
Main hazards	Damaging to Earth's protective ozone
Safety data sheet	See: data page
R-phrases	R44 R59
S-phrases	S9 S38
Flash point	Non-flammable
Lethal dose or concentration (LD, LC):
LC50 (median concentration)	760,000 ppm (mouse, 30 min) 800,000 ppm (rabbit, 30 min) 800,000 ppm (guinea pig, 30 min) 600,000 ppm (rat, 2 hr)
US health exposure limits (NIOSH):
PEL (Permissible)	TWA 1000 ppm (4950 mg/m3)
REL (Recommended)	TWA 1000 ppm (4950 mg/m3)
IDLH (Immediate danger)	15000 ppm
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Dichlorodifluoromethane (R-12) is a colorless gas usually sold under the brand name Freon-12, and a chlorofluorocarbon halomethane (CFC) used as a refrigerant and aerosol spray propellant. Complying with the , its manufacture was banned in developed countries (non-article 5 countries) in 1996, and developing countries (article 5 countries) in 2010 due to concerns about its damaging impact to the ozone layer. Its only allowed usage is as fire retardant in submarines and aircraft. It is soluble in many organic solvents. Dichlorodifluoromethane was one of the original propellants for Silly String. R-12 cylinders are colored white.

It can be prepared by reacting carbon tetrachloride with hydrogen fluoride in the presence of a catalytic amount of antimony pentachloride:

This reaction can also produce trichlorofluoromethane (CCl₃F), chlorotrifluoromethane (CClF₃) and tetrafluoromethane (CF₄).

Charles (Boss) Kettering, vice president of General Motors Research Corporation, was seeking a refrigerant replacement that would be colorless, odorless, tasteless, nontoxic, and nonflammable. He assembled a team that included Thomas Midgley, Jr., Albert Leon Henne, and Robert McNary. From 1930 to 1935, they developed dichlorodifluoromethane (CCl₂F₂ or R12), trichlorofluoromethane (CCl₃F or R11), chlorodifluoromethane (CHClF₂ or R22), trichlorotrifluoroethane (CCl₂FCClF₂ or R113), and dichlorotetrafluoroethane (CClF₂CClF₂ or R114), through Kinetic Chemicals which was a joint venture between DuPont and General Motors.