Question

State reasons for the following:
$S{F_6}$ is kinetically inert substance

Answer 1

Sulphur hexafluoride ( $S{F_6}$ ) is an inorganic, colourless, odourless, non-inflammable, non-toxic and hypervalent molecule. It is usually used as an electrical insulator and arc suppressant. It has a density higher than air and is usually transported as liquefied compressed gas.

Complete step by step solution:
Sulphur hexafluoride ( $S{F_6}$ ) has an octahedral geometry where the sulphur atom is being surrounded by six fluorine atoms. Sulphur hexafluoride ( $S{F_6}$ ) is usually prepared by exposing sulphur ( ${S_8}$ ) to fluorine ( ${F_2}$ ). It is an inorganic non - polar gas. $S{F_6}$ is $s{p^3}{d^2}$ hybridised and during its formation the central sulphur atom is in its ground state having $3{s^2}3{p^4}$ configuration. It consists of six $s{p^3}{d^2}$ hybridised orbitals that are projected towards six corners of a regular octahedron.
In $S{F_6}$ the central sulphur atom is sterically surrounded by the protection of six fluorine ( $F$ ) atoms where the $F - S - F$ bonds are slated to be at an angle of $90^\circ$ . The fluorine atom surrounding the central sulphur atom protects the sulphur atom without allowing the water molecules to get in. Also, fluorine doesn’t have vacant $d -$ orbitals to accept the electron which is being donated by ${H_2}O$ .
Thus $S{F_6}$ stays to be kinetically inert.

Note:
$S{F_6}$ is a type of greenhouse gas which is colourless, odourless, non-toxic and non – flammable. It is inert in nature in the troposphere and stratosphere. $S{F_6}$ is commonly used as a high voltage dielectric in high voltage supplies.