XeO3 Lewis structure

XeO₃ (xenon trioxide) has one xenon atom and three oxygen atoms.

In the XeO₃ Lewis structure, there are three double bonds around the xenon atom, with three oxygen atoms attached to it. Each oxygen atom has two lone pairs, and the xenon atom has one lone pair.

Alternative method: Lewis structure of XeO₃

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, xenon lies in group 18, and oxygen lies in group 16.

Hence, xenon has eight valence electrons and oxygen has six valence electrons.

Since XeO₃ has one xenon atom and three oxygen atoms, so…

Valence electrons of one xenon atom = 8 × 1 = 8
Valence electrons of three oxygen atoms = 6 × 3 = 18

And the total valence electrons = 8 + 18 = 26

Learn how to find: Oxygen valence electrons

• Second, find the total electron pairs

We have a total of 26 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 26 ÷ 2 = 13

• Third, determine the central atom

We have to place the least electronegative atom at the center.

Since xenon is less electronegative than oxygen, assume that the central atom is xenon.

Therefore, place xenon in the center and oxygens on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 13 electron pairs. And three Xe — O bonds are already marked. So we have to only mark the remaining ten electron pairs as lone pairs on the sketch.

Also remember that xenon is a period 5 element, so it can keep more than 8 electrons in its last shell. And oxygen is a period 2 element, so it can not keep more than 8 electrons in its last shell.

Always start to mark the lone pairs from outside atoms. Here, the outside atoms are oxygens.

So for each oxygen, there are three lone pairs, and for xenon, there is one lone pair.

Mark the lone pairs on the sketch as follows:

Formal charge

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For xenon atom, formal charge = 8 – 2 – ½ (6) = +3

For each oxygen atom, formal charge = 6 – 6 – ½ (2) = -1

Here, both xenon and oxygen atoms have charges, so mark them on the sketch as follows:

The above structure is not a stable Lewis structure because both xenon and oxygen atoms have charges. Therefore, reduce the charges (as below) by converting lone pairs to bonds.

Convert a lone pair of the oxygen atom to make a new Xe — O bond with the xenon atom as follows:

Since there are charges on xenon and oxygen atoms, again convert a lone pair of the oxygen atom to make a new Xe — O bond with the xenon atom as follows:

There are still charges on xenon and oxygen atoms, so again convert a lone pair of the oxygen atom to make a new Xe — O bond with the xenon atom as follows:

Final structure

The final structure of XeO₃ involves a central xenon atom connected to three oxygen atoms through double covalent bonds. In this arrangement, the xenon atom utilizes an expanded octet to accommodate its valence electrons while maintaining one lone pair, and each oxygen atom completes its octet with two lone pairs. By forming double bonds rather than single bonds, the molecule effectively reduces the formal charges of all atoms to zero, leading to a much more stable and energetically favorable state. Consequently, this specific distribution of electrons represents the definitive and most stable Lewis representation of xenon trioxide.

Next: PBr₃ Lewis structure

External video

• XeO3 Lewis Structure – How to Draw the Lewis Structure for XeO3 – YouTube • Wayne Breslyn

External links

• https://topblogtenz.com/xeo3-lewis-structure-molecular-geometry-polar-or-nonpolar-hybridization/
• https://lambdageeks.com/xeo3-lewis-structure/
• https://www.thegeoexchange.org/chemistry/bonding/Lewis-Structures/XeO3-lewis-structure.html