Editing Chlorofluorocarbon (section)

== Structure, properties and production ==
{{Main|Organofluorine chemistry}}
As in simpler [[alkanes]], carbons in CFCs bond with [[tetrahedral]] symmetry. Because the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each other, methane-derived CFCs deviate from perfect tetrahedral symmetry.<ref>{{cite book |doi=10.1002/14356007.a11_349 |chapter=Fluorine Compounds, Organic |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2000 |last1=Siegemund |first1=Günter |last2=Schwertfeger |first2=Werner |last3=Feiring |first3=Andrew |last4=Smart |first4=Bruce |last5=Behr |first5=Fred |last6=Vogel |first6=Herward |last7=McKusick |first7=Blaine |isbn=978-3-527-30385-4 }}</ref>

The physical properties of CFCs and HCFCs can be affected by changes in the number and identity of the [[halogen]] atoms. They are generally volatile, but less so than their parent alkanes. The decreased volatility is attributed to the molecular polarity induced by the [[halide]]s, which induces intermolecular interactions. Thus, methane boils at −161&nbsp;°C whereas the fluoromethanes boil between −51.7 ({{chem2|CF2H2}}) and −128&nbsp;°C ({{chem2|CF4}}). CFCs still have higher boiling points because the chloride is even more polarizable than fluoride. Because of their polarity, CFCs are useful solvents, and their boiling points make them suitable as refrigerants. CFCs are far less flammable than methane, in part because they contain fewer C–H bonds and in part because, in the case of the chlorides and bromides, the released halides quench the free radicals that sustain flames.

The densities of CFCs are higher than their corresponding alkanes. In general, the density of these compounds correlates with the number of chlorides.

CFCs and HCFCs are usually produced by halogen exchange starting from chlorinated methanes and ethanes. Written below is the synthesis of [[chlorodifluoromethane]] from [[chloroform]]:
:{{chem2|HCCl3 + 2 HF -> HCF2Cl + 2 HCl}}
Brominated derivatives are generated by free-radical reactions of hydrochlorofluorocarbons, replacing C–H bonds with C–Br bonds. The production of the [[anesthetic]] [[halothane|2-bromo-2-chloro-1,1,1-trifluoroethane]] ("halothane") is written out below:
:{{chem2|CF3CH2Cl + Br2 -> CF3CHBrCl + HBr}}