So you have seen the above image by now, right?
Let me explain the above image in short.
BrCl lewis structure has one Bromine atom (Br) and one Chlorine atom (Cl) which contain a single bond between them. There are 3 lone pairs on both the Bromine atom (Br) as well as Chlorine atom (Cl).
If you haven’t understood anything from the above image of BrCl lewis structure, then just stick with me and you will get the detailed step by step explanation on drawing a lewis structure of BrCl.
So let’s move to the steps of drawing the lewis structure of BrCl.
Steps of drawing BrCl lewis structure
Step 1: Find the total valence electrons in BrCl molecule
In order to find the total valence electrons in a BrCl molecule, first of all you should know the valence electrons present in the bromine atom as well as chlorine 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 bromine as well as chlorine using a periodic table.
Total valence electrons in BrCl molecule
→ Valence electrons given by bromine atom:
Bromine is a group 17 element on the periodic table.  Hence the valence electrons present in bromine is 7.
You can see the 7 valence electrons present in the bromine atom as shown in the above image.
→ Valence electrons given by chlorine atom:
Chlorine is group 17 element on the periodic table.  Hence the valence electrons present in chlorine is 7.
You can see the 7 valence electrons present in the chlorine atom as shown in the above image.
Total valence electrons in BrCl molecule = valence electrons given by 1 bromine atom + valence electrons given by 1 chlorine atom = 7 + 7 = 14.
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 BrCl. It has only two atoms, so you can select any of the atoms as a center atom.
Let’s assume the bromine atom as a central atom.
(You should assume the less electronegative atom as a center atom).
Step 3: Connect each atoms by putting an electron pair between them
Now in the BrCl molecule, you have to put the electron pairs between the bromine atom (Br) and chlorine atom (Cl).
This indicates that the bromine (Br) and chlorine (Cl) are chemically bonded with each other in a BrCl 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 BrCl molecule, we have assumed the bromine atom as a center atom. So the chlorine is the outer atom.
Hence you have to make the chlorine atom stable.
You can see in the below image that the chlorine 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 BrCl molecule.
The BrCl molecule has a total 14 valence electrons and out of these, only 8 valence electrons are used in the above sketch.
So the number of electrons which are left = 14 – 8 = 6.
You have to put these 6 electrons on the bromine atom in the above sketch of BrCl molecule.
Now let’s proceed to the next step.
Step 5: 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 BrCl.
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 bromine (Br) atom as well as chlorine (Cl) atoms present in the BrCl molecule.
For calculating the formal charge, you have to use the following formula;
Formal charge = Valence electrons – (Bonding electrons)/2 – Nonbonding electrons
For Bromine (Br) atom:
Valence electrons = 7 (because bromine is in group 17)
Bonding electrons = 6
Nonbonding electrons = 4
For Chlorine (Cl) atom:
Valence electrons = 7 (because chlorine is in group 17)
Bonding electrons = 2
Nonbonding electrons = 6
From the above calculations of formal charge, you can see that the bromine (Br) atom as well as chlorine (Cl) atom has a “zero” formal charge.
This indicates that the above lewis structure of BrCl is stable and there is no further change in the above structure of BrCl.
In the above lewis dot structure of BrCl, you can also represent each bonding electron pair (:) as a single bond (|). By doing so, you will get the following lewis structure of BrCl.
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:
|C2H2Br2 Lewis Structure
|SbCl5 Lewis Structure
|CH3SH Lewis Structure
|KrF4 Lewis Structure
|TeCl4 Lewis Structure
|AsO4 3- Lewis Structure
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. He is a founder of Pediabay and is passionate about helping students through his easily digestible explanations.
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