Definition Of Chlorofluorocarbons

Definition Of Chlorofluorocarbons

A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, and fluorine, produced as a volatile derivative of methane, ethane, and propane

More About Chlorofluorocarbons

• Chlorofluorocarbons are also commonly known as Freon
• The most common representative is dichlorodifluoromethane
• Many Chlorofluorocarbons have been widely used as refrigerants, propellants (in aerosol applications), and solvents
• The manufacture of such compounds (Chlorofluorocarbons) has been phased out under the Montreal Protocol, and are being replaced with products such as HFCs, hydrocarbons, and CO₂, because Chlorofluorocarbons contribute to ozone depletion in the upper atmosphere
• As in simpler alkanes, carbon in the Chlorofluorocarbons and the HCFCs is tetrahedral
• Since the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each other, the methane-derived Chlorofluorocarbons deviate from perfect tetrahedral symmetry
• These Chlorofluorocarbons are less volatile
• The decreased volatility is attributed to the molecular polarity induced by the halides, which induces intermolecular interactions
• The densities of Chlorofluorocarbons are higher than their corresponding alkanes
• The use of Chlorofluorocarbons has been heavily regulated because of their destructive effects on the ozone layer
• Freon is a trade name for a group of Chlorofluorocarbons which are used primarily as refrigerants
• Chlorofluorocarbons also have uses in fire-fighting and as propellants in aerosol cans
• Bromomethane is widely used as a fumigant
• Dichloromethane is a versatile industrial solvent
• An effective exchange agent was developed to replace chloride in carbon tetrachloride with fluoride to synthesize CFC-11 (CCl₃F) and CFC-12 (CCl₂F₂)
• Later on Chlorofluorocarbons was used industrially as a refrigerant
• Since the late 1970s, the use of Chlorofluorocarbons has been heavily regulated because of their destructive effects on the ozone layer
• The Chlorofluorocarbons diffuse into upper stratosphere
• Once in the stratosphere, the sun's ultraviolet radiation is strong enough to cause the homolytic cleavage of the C-Cl bond
• Chlorofluorocarbons react there with the ozone layer and cause its depletion
• As a result, more ultraviolet rays of sun reach the earth, and cause skin cancer
• Work on alternatives for chlorofluorocarbons in refrigerants began in the late 1970s after the first warnings of damage to stratospheric ozone were published
• This anthropogenic compound is also a greenhouse gas, with a much higher potential to enhance the greenhouse effect than CO₂
• The hydro chlorofluorocarbons (HCFCs) are less stable in the lower atmosphere, enabling them to break down before reaching the ozone layer

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