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Lewis structure

Lewis structure of XeF₆

50 valence electrons. Six Xe-F single bonds, with one lone pair on Xe, so Xe has 14 electrons around it (an expanded octet).

FFFXeFFF
  • Xe
  • F
  • lone pair

XeF₆Xenon hexafluoride

Distorted octahedral

AB₆E: 6 bond pairs, 1 lone pair

  • Hybridisationsp³d³
  • Bond angleno single angle
  • Polarityslightly polar

Lewis structure

50 valence electrons
XeFFFFFF

Formal charges: none

Why this shape

  1. Xe has 8 valence electrons. It uses six in six single bonds to F, so two are left as one lone pair.
  2. Steric number = six sigma bonds + one lone pair = 7, so Xe is sp³d³ hybridised.
  3. Seven electron pairs point to the corners of a pentagonal bipyramid (pentagonal bipyramidal electron geometry). With one lone pair in place of atoms, the atoms make a distorted octahedral shape.
  4. The lone pair pushes the six bonds out of a perfect octahedron.
  5. Repulsion falls in the order lone pair to lone pair > lone pair to bond pair > bond pair to bond pair. The lone pair pushes the bond pairs closer, so the angle is no single angle.
  6. XeF₆ is slightly polar (distorted octahedral, the dipole is very small).
Working

How to draw it

  1. Count the valence electrons: Xe 8 + 6 × F 7 = 50 valence electrons, 25 pairs.
  2. Put Xe in the middle and join it to the six outer atoms with single bonds.
  3. Give each outer atom lone pairs until it has an octet (H needs only two electrons), then put any electrons left over on the central atom.
  4. Result: six Xe-F single bonds, with one lone pair on Xe, so Xe has 14 electrons around it (an expanded octet).
  5. Formal charge = valence electrons − lone pair electrons − number of bonds. Here: none.

Class 11, Chapter 4 Chemical Bonding and Molecular Structure.

Questions

Lewis structure of XeF6: quick answers

How many valence electrons are in XeF6?

Xe 8 + 6 × F 7 = 50 valence electrons, 25 pairs.

What are the formal charges in the Lewis structure of XeF6?

Every atom has a formal charge of zero.

How many lone pairs are in the Lewis structure of XeF6?

19 in all, 1 of them on the central Xe.

Try any molecule