Q113 E - Chemistry (OpenStax)

Question

Indicate whether each of the following molecules is polar and non-polar.

         (a) \(Xe{F_2}\)               (b) \({\rm{Xe}}{{\rm{F}}_{\rm{4}}}\)               (c) \({\rm{Xe}}{{\rm{O}}_{\rm{3}}}\)                (d)  \({\rm{XeO}}{{\rm{F}}_{\rm{4}}}\)    

 

Step-by-Step Solution

Answer

Among the four given molecules (a) \(Xe{F_2}\) and (b) \({\rm{Xe}}{{\rm{F}}_{\rm{4}}}\) are non-polar, whereas (c) \({\rm{Xe}}{{\rm{O}}_{\rm{3}}}\)  and   (d) \({\rm{XeO}}{{\rm{F}}_{\rm{4}}}\) are polar. 

Step 1: Polar and non-polar molecule :

To understand whether a molecule is polar or non-polar, first we have understand its Lewis structures and electronegativity of that element. Polar molecules are usually asymmetric, they contain lone pair of electrons on a central atom.

Step 2: Explanation :

Let us see all the options: 

(a) \(Xe{F_2}\) has Linear structure and symmetrical in nature.  It has two polar Xe – F bond and they are opposite to each other .So, bond dipoles cancel each other. That’s why it is a non-polar molecule. 

(b) \({\rm{Xe}}{{\rm{F}}_{\rm{4}}}\) has Square planar str. and symmetrical in nature. It has four Xe – F bond, they are opposite to each other.So, bond dipoles cancel each other. That’s why it is non-polar molecule.

 (c) \({\rm{Xe}}{{\rm{O}}_{\rm{3}}}\) molecule is a polar molecule. It contains three polar Xe – O bonds that are asymmetrically arranged around the central metal (Xe) atom. Bond dipoles do not cancel each other but add to a net dipole with the Xe atom at the positive end.

(d) \({\rm{XeO}}{{\rm{F}}_{\rm{4}}}\) , it is a polar molecule  with square pyramidal shape . There is a lone pair attached to Xe, the opposite side of o atom .The dipoles are not cancel each other.