Compounds that contain many C-F bonds often have distinctive properties, e.g., enhanced[clarification needed] stability, volatility, and hydrophobicity.
[4] Its strength is a result of the electronegativity of fluorine imparting partial ionic character through partial charges on the carbon and fluorine atoms, which shorten and strengthen the bond (compared to carbon-hydrogen bonds) through favorable covalent interactions.
As the high electronegativity of fluorine reduces the polarizability of the atom,[1] fluorocarbons are only weakly susceptible to the fleeting dipoles that form the basis of the London dispersion force.
As a result, fluorocarbons have low intermolecular attractive forces and are lipophobic in addition to being hydrophobic and non-polar.
It has been suggested that an atmosphere containing a significant percentage of perfluorocarbons on a space station or similar would prevent fires altogether.
[12] The table shows values for the mole fraction, x1, of nitrogen dissolved, calculated from the Blood–gas partition coefficient, at 298.15 K (25 °C), 0.101325 MPa.
Electrochemical fluorination (ECF) (also known as the Simons' process) involves electrolysis of a substrate dissolved in hydrogen fluoride.
To make perfluorohexane, trihexylamine is used, for example: The perfluorinated amine will also be produced: Fluoroalkanes are generally inert and non-toxic.
[21] Low-boiling perfluoroalkanes are potent greenhouse gases, in part due to their very long atmospheric lifetime, and their use is covered by the Kyoto Protocol.
[citation needed][22] The global warming potential (compared to that of carbon dioxide) of many gases can be found in the IPCC 5th assessment report,[23] with an extract below for a few perfluoroalkanes.
The aluminium smelting industry has been a major source of atmospheric perfluorocarbons (tetrafluoromethane and hexafluoroethane especially), produced as by-product of the electrolysis process.
[1] Unsaturated fluorocarbons have a driving force towards sp3 hybridization due to the electronegative fluorine atoms seeking a greater share of bonding electrons with reduced s character in orbitals.
Perfluoroaromatic compounds can be manufactured via the Fowler process, like fluoroalkanes, but the conditions must be adjusted to prevent full fluorination.
A third route is defluorination of the fluoroalkane; for example, octafluorotoluene can be made from perfluoromethylcyclohexane by heating to 500 °C with a nickel or iron catalyst.