Lewis Structure of BrCl2- (With 5 Simple Steps to Draw!)

Lewis Structure of BrCl2-

I’m super excited to teach you the lewis structure of BrCl2- ion in just 5 simple steps.

Infact, I’ve also given the step-by-step images for drawing the lewis dot structure of BrCl2- ion.

So, if you are ready to go with these 5 simple steps, then let’s dive right into it!

Lewis structure of BrCl2- ion contains two single bonds between the Bromine (Br) atom and each Chlorine (Cl) atom. The Bromine atom (Br) is at the center and it is surrounded by 2 Chlorine atoms (Cl). The Bromine atom as well as both the Chlorine atoms have 3 lone pairs. The Bromine atom has -1 formal charge.

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 BrCl2- ion).

5 Steps to Draw the Lewis Structure of BrCl2- ion

Step #1: Calculate the total number of valence electrons

Here, the given ion is BrCl2- ion. In order to draw the lewis structure of BrCl2-, first of all you have to find the total number of valence electrons present in the BrCl2- ion.
(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 BrCl2- ion

  • For Bromine:

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

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

  • For Chlorine:

Chlorine is a group 17 element on the periodic table. [2]

Hence, the valence electron present in chlorine is 7 (see below image).

Hence in a BrCl2- ion, 

Valence electrons given by Bromine (Br) atom = 7
Valence electrons given by each Chlorine (Cl) atom = 7
Electron due to -1 charge, 1 more electron is added
So, total number of Valence electrons in BrCl2- ion = 7 + 7(2) + 1 = 22

Step #2: Select the center atom

While selecting the atom, always put the least electronegative atom at the center. 

Here in the BrCl2- ion, if we compare the bromine atom (Br) and chlorine atom (Cl), then the bromine is less electronegative than chlorine.

So, bromine should be placed in the center and the remaining 2 chlorine atoms will surround it.

step 1

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

Now in the above sketch of BrCl2, put the two electrons (i.e electron pair) between each bromine atom and chlorine atom to represent a chemical bond between them.

step 2

These pairs of electrons present between the Bromine (Br) and Chlorine (Cl) atoms form a chemical bond, which bonds the bromine and chlorine atoms with each other in a BrCl2 molecule.

Step #4: Complete the octet (or duplet) on outside atoms. 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 BrCl2, the outer atoms are chlorine atoms.

So now, you have to complete the octet on these chlorine atoms (because chlorine requires 8 electrons to have a complete outer shell).

step 3

Now, you can see in the above image that all the chlorine atoms form an octet.

Also, only 16 valence electrons of BrCl2- ion are used in the above structure.

But there are total 22 valence electrons in BrCl2- ion (as calculated in step #1).

So the number of electrons left to be kept on the central atom = 22 – 16 = 6.

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

step 4

Now, let’s move to the next step.

Step #5: 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 bromine atom (Br) as well as each chlorine atom (Cl).

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

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

step 5
  • For Bromine:
    Valence electron = 7 (as it is in group 17)
    Nonbonding electrons = 6
    Bonding electrons = 4
  • For Chlorine:
    Valence electron = 7 (as it is in group 17)
    Nonbonding electrons = 6
    Bonding electrons = 2
Formal charge=Valence electronsNonbonding electrons(Bonding electrons)/2
Br=764/2=-1
Cl=762/2=0

Let’s keep these charges on the atoms in the above lewis structure of BrCl2- ion.

step 6

As you can see in the above sketch, there is one -ve charge on the bromine atom, which indicates the -1 formal charge on the BrCl2 molecule.

Hence, the above lewis structure of BrCl2- ion is the stable lewis structure.

Each electron pair (:) in the lewis dot structure of BrCl2- ion represents the single bond ( | ). So the above lewis dot structure of BrCl2- ion can also be represented as shown below.

brcl2- lewis structure

Related lewis structures for your practice:
Lewis Structure of CF2S
Lewis Structure of PI5
Lewis Structure of SO2F2
Lewis Structure of OPBr3
Lewis Structure of PH2- 


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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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