Question

Complete the following reaction. $Xe{F_4} + Sb{F_5} \to $

Answer 1

Hint: Here we are asked to complete the reaction. In order to predict the reaction, we must first identify the nature of the given species. In this case, $Sb{F_5}$ is a Lewis acid species which can accept a pair of electrons from another species which has the capability to donate a pair of its electrons.

Complete step by step solution:
$Xe{F_4}$ forms an additional compound or adduct with $Sb{F_5}$. This kind of a reaction between the two compounds is possible because$Xe{F_4}$ is a strong fluorinating agent and $Sb{F_5}$ is a strong Lewis acid. So, $Sb{F_5}$ accepts the ${F^ - }$ donated by $Xe{F_4}$ to form the adduct.
Hence, the reaction between $Xe{F_4}$ and $Sb{F_5}$ can be depicted as follows:

$Xe{F_4} + Sb{F_5} \to {\left[ {Xe{F_3}} \right]^ + }{\left[ {Sb{F_6}} \right]^ - }$

Additional Information:
$Xe{F_4}$ has a square planar shape due to $s{p^3}{d^2}$ hybridization of Xe. It adopts an octahedral geometry with two trans positions occupied by two lone pairs of electrons.
$Sb{F_5}$ is a strong Lewis acid. It adopts a trigonal bipyramidal structure. It is exceptionally reactive towards Lewis bases like ${F^ - }$ to give rise to a very stable anion, hexafluoroantimonate, represented as ${\left[ {Sb{F_6}} \right]^ - }$ .
Lewis acids and bases:
Lewis acids are defined as species which can accept a pair of electrons, also known as electrophiles (meaning, electron attracting or electron loving). They are positively charged or neutral atoms, ions or groups of atoms which are electron deficient. Examples: ${H^ + },{H_3}{O^ + },N{O_2},F{e^{2 + }},C{u^{2 + }}$ etc.
Lewis bases are defined as species which can donate a pair of electrons, also known as nucleophiles (meaning, nucleus attracting or nucleus loving). They are negatively charged or neutral atoms, ions or groups of atoms which are electron rich. Examples: $C{l^ - },B{r^ - },C{N^ - },O{H^ - },N{H_3},{H_2}O$ etc.

Note: The nature of the reacting species has to be correctly identified. This helps us to predict the possible ways in which the species can react with each other. Remember that not all reactions produce two or more products. Reactions like these lead to the formation of adducts.