XEF4 polarity

[Ibraiz]

Why is XeF4 is non-polar. It contains two lone pair of electrons. If they are non-polar because of the reason that it is octahedral in shape and contain lone pairs on top and bottom then how do we know that they are on top and bottom not both of them on the same side?
I remember coming across a question where Xe had both the lone pairs on the top and in this question they are on the same side.



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[Charmm]

XeF4 is a molecule with octahderal ELECTRON PAIR geometry and square plannar MOLECULAR geometry, any molecule with central atom having dsp3 hybridization is considrred octahedral electron geometry. The following molecules all have octahderal electron geometry but different molecular geometries:

XeF6 has no lone pair electron pairs on Xe, therefore it is octahedral and nonpolar

Xef5 has one lone pair on Xe, it is square pyramidal and polar

XeF4 has two lone pairs on Xe, it is square plannar and nonpolar because the lone pairs are opposite to each other and their attraction/repulsion is cancelled.

 

[Cool Beans]

XeF4 is a molecule with octahderal ELECTRON PAIR geometry and square plannar MOLECULAR geometry, any molecule with central atom having dsp3 hybridization is considrred octahedral electron geometry. The following molecules all have octahderal electron geometry but different molecular geometries:

XeF6 has no lone pair electron pairs on Xe, therefore it is octahedral and nonpolar

Xef5 has one lone pair on Xe, it is square pyramidal and polar

XeF4 has two lone pairs on Xe, it is square plannar and nonpolar because the lone pairs are opposite to each other and their attraction/repulsion is cancelled.

d2sp3 hybridization actually...great explanation otherwise!

 

[Ibraiz]

Thanks for the explanation. Does it ever happen that a molecule is d2sp3 and it has two electron pair but it is still polar?

Is it possible with dsp3?

 

[drpj]

The easiest way I remember what molecules are polar is by drawing it out and seeing which molecule has ONE lone pair of electrons bonded to the central
atom. In this case XeF4 has two lone pairs of electrons.

 

[Charmm]

Thanks for d2sp3 note, somehow I missed the 2!
But for DAT, always d2sp3 with two lone pairs will be nonpolar. In advanced inorganic courses however, some extreme cases are shown but you dont need to know those. In my DAT, NO3 (-) was a question
do you think it is polar or nonpolar?

 

[nyr201]

the net dipole with the F's are zero and u have 2 lone pairs, opposing lone pairs cancel each other out so no dipole there either so u have a non-polar molecule