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Greenhouse gas
1,1,2-Trichloro-1,2,2-trifluoroethane
Другие языки:

1,1,2-Trichloro-1,2,2-trifluoroethane

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1,1,2-Trichloro-1,2,2-trifluoroethane
1,1,2-Trichloro-1,2,2-trifluoroethane skeletal.svg
1,1,2-Trichloro-1,2,2-trifluoroethane 3D.png
Names
Preferred IUPAC name
1,1,2-Trichloro-1,2,2-trifluoroethane
Other names
CFC-113
Freon 113
Frigen 113 TR
Freon TF
Valclene
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.000.852
PubChem CID
UNII
  • InChI=1S/C2Cl3F3/c3-1(4,6)2(5,7)8 checkY
    Key: AJDIZQLSFPQPEY-UHFFFAOYSA-N checkY
  • InChI=1/C2Cl3F3/c3-1(4,6)2(5,7)8
    Key: AJDIZQLSFPQPEY-UHFFFAOYAE
  • ClC(F)(F)C(Cl)(Cl)F
Properties
CClF2CCl2F
Molar mass 187.37 g·mol−1
Appearance Colorless liquid
Odor like carbon tetrachloride
Density 1.56 g/mL
Melting point −35 °C (−31 °F; 238 K)
Boiling point 47.7 °C (117.9 °F; 320.8 K)
170 mg/L
Vapor pressure 285 mmHg (20 °C)
Thermal conductivity 0.0729 W m−1 K−1 (300 K)
Hazards
Lethal dose or concentration (LD, LC):
250,000 ppm (mouse, 1.5 hr)
87,000 (rat, 6 hr)
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 1000 ppm (7600 mg/m3)
REL (Recommended)
 TWA 1000 ppm (7600 mg/m3) ST 1250 ppm (9500 mg/m3)
IDLH (Immediate danger)
 2000 ppm
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

1,1,2-Trichloro-1,2,2-trifluoroethane, also called trichlorotrifluoroethane or CFC-113, is a chlorofluorocarbon. It has the formula Cl2FC−CClF2. This colorless, volatile liquid is a versatile solvent.

Atmospheric reactions

CFC-113 measured by the Advanced Global Atmospheric Gases Experiment (AGAGE) in the lower atmosphere (troposphere) at stations around the world. Abundances are given as pollution free monthly mean mole fractions in parts-per-trillion.
Atmospheric concentration of CFC-113 since year 1992.

CFC-113 is a very unreactive chlorofluorocarbon. It remains in the atmosphere about 90 years, sufficiently long that it will cycle out of the troposphere and into the stratosphere. In the stratosphere, CFC-113 can be broken up by ultraviolet radiation (where sunlight in the 190-225 nm (UV) range), generating chlorine radicals (Cl•), which initiate degradation of ozone requiring only a few minutes:

CClF2CCl2F → C2F3Cl2 + Cl•
Cl• + O3 → ClO• + O2

This reaction is followed by:

ClO• + O → Cl• + O2

The process regenerates Cl• to destroy more O3. The Cl• will destroy an average of 100,000 O3 molecules during its atmospheric lifetime of 1–2 years. In some parts of the world, these reactions have significantly thinned the Earth's natural stratospheric ozone layer that shields the biosphere against solar UV radiation; increased UV levels at the surface can cause skin cancer or even blindness.

Uses

CFC-113 was one of the most heavily produced CFCs. In 1989, an estimated 250,000 tons were produced. It has been used as a cleaning agent for electrical and electronic components. CFC-113 is one of the three most popular CFCs, along with CFC-11 and CFC-12.

CFC-113’s low flammability and low toxicity made it ideal for use as a cleaner for delicate electrical equipment, fabrics, and metals. It would not harm the product it was cleaning, ignite with a spark or react with other chemicals.

CFC-113 in laboratory analytics has been replaced by other solvents.

Reduction of CFC-113 with zinc gives chlorotrifluoroethylene:

CFCl2−CClF2 + Zn → CClF=CF2 + ZnCl2

Dangers

Aside from its immense environmental impacts, Freon 113, like most chlorofluoroalkanes, forms phosgene gas when exposed to a naked flame.

See also


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