Is SF6 Polar or Nonpolar?

Answer: SF6 is a nonpolar molecule due to the symmetrical placement of all of the fluorines around the central sulfur atom. This arrangement at perpendicular (90˚) angles ensures that the pull for electrons by fluorines on one side is balanced by fluorines pulling on the other side. This results in there being no permanent dipole within the structure. 

Due to the large number of fluorine atoms, there is a larger amount of partial negative charge around each of them. This decreases the capacity of the molecule to form solid structures. As a result the structure has a melting point of -64°C and boiling point of -51°C which is quite low considering the number of electrons within the structure. Furthermore, due to the symmetrical molecular configuration, Sulfur Hexafluoride does not mix with polar solvents but it does with nonpolar solvents. However, the gas does have a much higher density than air. As a result SF6 is an incredibly potent greenhouse gas, one of the most dangerous ever measured. This is why it needs to be handled carefully and properly disposed of. Please read on to learn more about the different uses of SF6. 

If you are interested in learning more about why SF6 is covalent as opposed to ionic, then feel free to check out this article.

SF6 Ball and Stick Model. Created with MolView.

How is SF6 utilized in the real world? 

Sulfur hexafluoride is most commonly utilized as a pressurized insulating gas in rooms/gadgets where electrical equipment is stored. This is because the material is very dielectrically strong which means that it can withstand the formation of a large electric field without becoming conductive itself. This is due to the high electronegativity of the many fluorines on the molecule. Over 8,000 tons of 80% of the SF6 gas produced is utilized in this application. Sulfur hexafluoride may also be used in ultrasound imaging, tracing applications and other niche uses.