Draw the Lewis structure of HXeSH and describe the electron and molecular geometry around the central atom according to VSEPR theory?

1 Answer
Apr 5, 2016

I don't know why you have that image, but anyways, HXeSH...

  • Xe is a noble gas which contributes 8 valence electrons to the lewis structure.
  • S is group 16, which contributes 6 electrons to the lewis structure.
  • Each H contributes 1 electron.

So, we have a total of 16 electrons to distribute. Note that the formula could have been written H2XeS, but it wasn't. That means this is the structural formula, and so you already have the lewis structure.

HXeSH

is the skeleton structure. We've accounted for 6 valence electrons. We would be able to add four more valence electrons onto sulfur and four more onto xenon, accounting for a total of 14 so far.

Since it wouldn't make sense for sulfur to get the remaining 2 electrons (xenon is larger and can hold more electrons around it more easily), we put the remaining 2 on Xe.

Thus, the structure looks like this:

Since Xe has five electron groups around it, if we treat it as a central atom, it has a trigonal bipyramidal electron geometry, and a linear molecular geometry because it only has two bonding groups.

Since S has four electron groups around it, if we treat it as a central atom, it has a tetrahedral electron geometry, and a bent molecular geometry because it only has two bonding groups.

As for the formal charges, we have:

  • Xe owns 8 electrons (three lone pairs and one from each single bond) and needs 8, thus its formal charge is 88=0.
  • S owns 6 electrons (two lone pairs and one from each single bond) and needs 6, thus its formal charge is 88=0.
  • H owns 1 electron (from its single bond) and needs 1, thus its formal charge is 11=0.

Therefore, all formal charges have been minimized.