N2O5 Lewis structure

N₂O₅ (dinitrogen pentoxide) has two nitrogen atoms and five oxygen atoms.

In the N₂O₅ Lewis structure, there are two single bonds around the center oxygen atom, with two nitrogen atoms attached to it, and each nitrogen makes one single bond and one double bond with other two oxygen atoms. The oxygen atom with single bonds has three lone pairs, the oxygen atom with double bonds has two lone pairs, and the center oxygen atom also has two lone pairs.

Also, there is a negative (-1) charge on the two oxygen atoms with single bonds, and a positive (+1) charge on the two nitrogen atoms.

Alternative method: Lewis structure of N₂O₅

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, nitrogen lies in group 15, and oxygen lies in group 16.

Hence, nitrogen has five valence electrons and oxygen has six valence electrons.

Since N₂O₅ has two nitrogen atoms and five oxygen atoms, so…

Valence electrons of two nitrogen atoms = 5 × 2 = 10
Valence electrons of five oxygen atoms = 6 × 5 = 30

And the total valence electrons = 10 + 30 = 40

Learn how to find: Nitrogen valence electrons and Oxygen valence electrons

• Second, find the total electron pairs

We have a total of 40 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 = 40 ÷ 2 = 20

• Third, determine the central atom

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

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

Here, there are two nitrogen atoms, so we can assume any one as the central atom.

Let’s assume that the central atom is left nitrogen.

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

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 20 electron pairs. And six bonds are already marked. So we have to only mark the remaining fourteen electron pairs as lone pairs on the sketch.

Also remember that both (nitrogen and oxygen) are the period 2 elements, so they can not keep more than 8 electrons in their last shell.

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

So for each top oxygen, left oxygen, and right oxygen, there are three lone pairs. For center oxygen, there are two lone pairs, and for nitrogen, there is zero lone pair because all fourteen electron pairs are over.

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 each nitrogen atom, formal charge = 5 – 0 – ½ (6) = +2

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

For center oxygen atom, formal charge = 6 – 4 – ½ (4) = 0

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

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

Convert a lone pair of the top oxygen atom to make a new N — O bond with the left nitrogen atom as follows:

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

Final structure

The final structure of N₂O₅ contains two nitrogen atoms linked by a central bridging oxygen atom, with each nitrogen also bonded to two terminal oxygen atoms. Within this arrangement, each nitrogen forms a double bond with one terminal oxygen and a single bond with the other, allowing all atoms to satisfy the octet rule. This configuration results in formal charges of +1 on both nitrogen atoms and -1 on the two single-bonded terminal oxygens, while the bridging and double-bonded oxygens maintain a formal charge of zero. Because this distribution minimizes formal charges as much as possible for this specific connectivity, it represents the most stable and definitive Lewis representation of dinitrogen pentoxide.

Next: BeBr₂ Lewis structure

External video

• N2O5 Lewis Structure: How to Draw the Lewis Structure for N2O5 – YouTube • Wayne Breslyn

External links

• https://www.thegeoexchange.org/chemistry/bonding/Lewis-Structures/N2O5-lewis-structure.html
• https://www.chemistryscl.com/ask_questions/Q/inorganic/N2O5-resonance-structures/index.php
• https://lambdageeks.com/n2o5-lewis-structure/
• https://socratic.org/questions/57e925207c0149048a48aaea