O2 Lewis Structure in 6 Steps (With Images)

So you have seen the above image by now, right?

Let me explain the above image in short.

O2 lewis structure has two Oxygen atoms (O) which contain a double bond between them. There are 2 lone pairs on both the Oxygen atoms (O).

If you haven’t understood anything from the above image of O2 (oxygen) lewis structure, then just stick with me and you will get the detailed step by step explanation on drawing a lewis structure of O2.

So let’s move to the steps of drawing the lewis structure of O2.

Steps of drawing O2 lewis structure

Step 1: Find the total valence electrons in O2 molecule

In order to find the total valence electrons in O2 (oxygen) molecule, first of all you should know the valence electrons present in a single oxygen atom.
(Valence electrons are the electrons that are present in the outermost orbit of any atom.)

Here, I’ll tell you how you can easily find the valence electrons of oxygen using a periodic table.

Total valence electrons in O2 molecule

→ Valence electrons given by oxygen atom:

Oxygen is group 16 element on the periodic table. ^[1] Hence the valence electrons present in oxygen is 6.

You can see the 6 valence electrons present in the oxygen atom as shown in the above image.

Hence, 

Total valence electrons in O2 molecule = 6(2) = 12.

Step 2: Select the central atom

For selecting the center atom, you have to remember that the atom which is less electronegative remains at the center.

Now here the given molecule is O2 (oxygen). Both the atoms are same, so you can select any of the atoms as a center atom.

Let’s assume the right side oxygen as a central atom.

Step 3: Connect each atoms by putting an electron pair between them

Now in the O2 molecule, you have to put the electron pairs between both the oxygen atoms (O).

This indicates that both the oxygen (O) atoms are chemically bonded with each other in an O2 molecule.

Step 4: Make the outer atoms stable. Place the remaining valence electrons pair on the central atom.

Now in this step, you have to check the stability of the outer atom.

Here in the sketch of O2 molecule, we have assumed the right side oxygen atom as a center atom. So the left side oxygen is the outer atom.

Hence you have to make the left side oxygen stable.

You can see in the below image that the left side oxygen atom is forming an octet and hence it is stable.

Also, in step 1 we have calculated the total number of valence electrons present in the O2 molecule.

The O2 molecule has a total 12 valence electrons and out of these, only 8 valence electrons are used in the above sketch.

So the number of electrons which are left = 12 – 8 = 4.

You have to put these 4 electrons on the right side oxygen atom in the above sketch of O2 molecule.

Now let’s proceed to the next step.

Step 5: Check the octet on the central atom. If it does not have octet, then shift the lone pair to form a double bond or triple bond.

In this step, you have to check whether the central (i.e right side) oxygen atom (O) is stable or not.

In order to check the stability of this oxygen (O) atom, we have to check whether it is forming an octet or not.

Unfortunately, this oxygen atom is not forming an octet here. Oxygen has only 6 electrons and it is unstable.

Now to make this oxygen atom stable, you have to shift the electron pair from the left oxygen atom.

After shifting this electron pair, the right side oxygen atom will get 2 more electrons and thus its total electrons will become 8.

You can see from the above picture that the right side oxygen atom is forming an octet.

And hence this oxygen atom is stable.

Now let’s proceed to the final step to check whether the lewis structure of O2 is stable or not.

Step 6: Check the stability of lewis structure

Now you have come to the final step in which you have to check the stability of lewis structure of O2.

The stability of lewis structure can be checked by using a concept of formal charge.

In short, now you have to find the formal charge on both the oxygen (O) atoms present in the O2 molecule.

For calculating the formal charge, you have to use the following formula;

Formal charge = Valence electrons – (Bonding electrons)/2 – Nonbonding electrons

You can see the number of bonding electrons and nonbonding electrons in the image given below.

For Oxygen (O) atom:
Valence electrons = 6 (because oxygen is in group 16)
Bonding electrons = 4
Nonbonding electrons = 4

Formal charge	=	Valence electrons	–	(Bonding electrons)/2	–	Nonbonding electrons
O	=	6	–	4/2	–	4	=	0

From the above calculations of formal charge, you can see that both the oxygen (O) atoms have a “zero” formal charge.

This indicates that the above lewis structure of O2 is stable and there is no further change in the above structure of O2.

In the above lewis dot structure of O2, you can also represent each bonding electron pair (:) as a single bond (|). By doing so, you will get the following lewis structure of O2.

I hope you have completely understood all the above steps.

For more practice and better understanding, you can try other lewis structures listed below.

Try (or at least See) these lewis structures for better understanding:

CO lewis structure	CH4 lewis structure
BF3 lewis structure	NO3- lewis structure
O3 lewis structure	C2H2 lewis structure