1,1-Dichloro-1-fluoroethane is a haloalkane with the formula C
2H
3Cl
2F. It is one of the three isomers of dichlorofluoroethane. It belongs to the hydrochlorofluorocarbon (HCFC) family of man-made compounds that contribute significantly to both ozone depletion and global warming when released into the environment.
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| Names | |||
|---|---|---|---|
| Preferred IUPAC name 1,1-Dichloro-1-fluoroethane | |||
| Other names Dichlorofluoroethane; R-141b; HCFC-141b | |||
| Identifiers | |||
3D model (JSmol) | |||
| ChemSpider | |||
| ECHA InfoCard | 100.100.575 | ||
| EC Number |
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PubChem CID | |||
| RTECS number |
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| UNII | |||
| UN number | 9274 | ||
CompTox Dashboard (EPA) | |||
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| Properties | |||
| C2H3Cl2F | |||
| Molar mass | 116.94 g·mol−1 | ||
| Appearance | Colorless liquid, ethereal odor | ||
| Density | 1.25 g/cm3 at 20 °C[1] | ||
| Melting point | −103.5 °C (−154.3 °F; 169.7 K)[1] | ||
| Boiling point | 32 °C (90 °F; 305 K)[1] | ||
| 4 g/L (20 °C)[1] | |||
| Hazards | |||
| GHS labelling: | |||
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| Warning | |||
| H412, H420 | |||
| P273, P501, P502 | |||
| 532 °C (990 °F; 805 K)[1] | |||
| Explosive limits | 5.6–17.7% vol.[1] | ||
| Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 5 g/kg (rat, oral) | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |||
Physiochemical properties
1,1-Dichloro-1-fluoroethane can be a non-flammable, colourless liquid under room-temperature atmospheric conditions. The compound is very volatile with a boiling point of 32°C.[1][2] Its critical temperature is near 204°C.[3] Its smell has been described as "usually ethereal" (like ether).
Production and use
1,1-Dichloro-1-fluoroethane is mainly used as a solvent and foam blowing agent under the names R-141b and HCFC-141b. It is a class 2 ozone depleting substance undergoing a global phaseout from production and use under the Montreal Protocol since the late 1990s. It is being replaced by HFCs within some applications.[4]
Environmental effects
The concentration of HCFC-141b in the atmosphere grew to near 25 parts per trillion by year 2016.[5] It has an ozone depletion potential (ODP) of 0.12.[6] This is low compared to the ODP=1 of trichlorofluoromethane (CFC-11, R-11), which also grew about ten times more abundant in the atmosphere prior to introduction of HFC-141b and subsequent adoption of the Montreal Protocol.
HFC-141b is also a minor but potent greenhouse gas. It has an estimated lifetime of about 10 years and a 100-year global warming potential ranging 725 to 2500.[7][8] This compares to the GWP=1 of carbon dioxide, which had a much greater atmospheric concentration near 400 parts per million in year 2020.