Lewis Structure of I2 (With 6 Simple Steps to Draw!)

Lewis Structure of I2

Ready to learn how to draw the lewis structure of I2?


Here, I have explained 6 simple steps to draw the lewis dot structure of I2 (along with images).

So, if you are ready to go with these 6 simple steps, then let’s dive right into it!

Lewis structure of I2 (Iodine) contains one single bond between both the Iodine (I) atoms. And both the Iodine atoms have three lone pairs on it.

Let’s draw and understand this lewis dot structure step by step.

(Note: Take a pen and paper with you and try to draw this lewis structure along with me. I am sure you will definitely learn how to draw lewis structure of I2).

6 Steps to Draw the Lewis Structure of I2

Step #1: Calculate the total number of valence electrons

Here, the given molecule is I2 (Iodine). In order to draw the lewis structure of I2, first of all you have to find the total number of valence electrons present in the I2 molecule.
(Valence electrons are the number of electrons present in the outermost shell of an atom).

So, let’s calculate this first.

Calculation of valence electrons in I2

  • For Iodine:

Iodine is a group 17 element on the periodic table. [1]

Hence, the valence electrons present in iodine is 7 (see below image).

Hence, total number of Valence electrons in I2 molecule = 7(2) = 14

Step #2: Select the center atom

While selecting the atom, you have to put the least electronegative atom at the center. 

But here in the I2 molecule, both the atoms are same. So you can consider any of the atoms as a center atom.

step 1

So, let’s assume that the iodine which is on the right side is the central atom.

Step #3: Put two electrons between the atoms to represent a chemical bond

Now in the above sketch of I2 molecule, put the two electrons (i.e electron pair) between both the iodine atoms to represent a chemical bond between them.

step 2

These pair of electrons present between the Iodine (I) atoms form a chemical bond, which bonds both the iodine atoms with each other in a I2 molecule.

Step #4: Complete the octet (or duplet) on outside atom. If the valence electrons are left, then put the valence electrons pair on the central atom

Don’t worry, I’ll explain!

In the Lewis structure of I2, we have just assumed the right side iodine atom as a central atom and so the left side iodine atom is an outer atom.

So now, we have to complete the octet on this left side iodine atom.

step 3

Now, you can see in the above image that the outer iodine atom forms an octet.

Also, only 8 valence electrons of I2 molecule are used in the above structure.

But there are total 14 valence electrons in I2 molecule (as calculated in step #1).

So the number of electrons left to be kept on the central atom = 14 – 8 = 6.

So let’s keep these six electrons (i.e 3 electron pairs) on the central atom (i.e right side iodine atom).

step 4

Now, let’s move to the next step.

Step #5: Check whether the central atom has octet or not

In this step, we have to check whether the central atom (i.e right side iodine atom) has an octet or not. 

In simple words, we have to check whether the central Iodine (I) atom is having 8 electrons or not.

step 5

As you can see from the above image, the central atom (i.e right side iodine atom) has 8 electrons. So it fulfills the octet rule and this iodine atom is also stable.

Step #6: Final step – Check the stability of lewis structure by calculating the formal charge on each atom

Now, you have come to the final step and here you have to check the formal charge on the iodine atoms (I).

For that, you need to remember the formula of formal charge;

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

step 6
  • For Iodine:
    Valence electron = 7 (as it is in group 17)
    Nonbonding electrons = 6
    Bonding electrons = 2
Formal charge=Valence electronsNonbonding electrons(Bonding electrons)/2

So you can see above that the formal charge on both the iodine atoms are “zero”.

Hence, there will not be any change in the above structure and the above lewis structure of I2 is the final stable structure only.

Each electron pair (:) in the lewis dot structure of I2 represents the single bond ( | ). So the above lewis dot structure of I2 can also be represented as shown below.

I2 Lewis Structure

Related lewis structures for your practice:
Lewis structure of ICl3
Lewis structure of NOF
Lewis structure of ClF5
Lewis structure of IF4-
Lewis structure of PBr3

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Jay is an educator and has helped more than 100,000 students in their studies by providing simple and easy explanations on different science-related topics. With a desire to make learning accessible for everyone, he founded Knords Learning, an online learning platform that provides students with easily understandable explanations.

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