I’m super excited to teach you the lewis structure of BrF2- ion in just 5 simple steps.
Infact, I’ve also given the step-by-step images for drawing the lewis dot structure of BrF2- ion.
So, if you are ready to go with these 5 simple steps, then let’s dive right into it!
Lewis structure of BrF2- ion contains two single bonds between the Bromine (Br) atom and each Fluorine (F) atom. The Bromine atom (Br) is at the center and it is surrounded by 2 Fluorine atoms (F). The Bromine atom as well as both the Fluorine 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 BrF2- ion).
5 Steps to Draw the Lewis Structure of BrF2- ion
Step #1: Calculate the total number of valence electrons
Here, the given ion is BrF2- ion. In order to draw the lewis structure of BrF2-, first of all you have to find the total number of valence electrons present in the BrF2- 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 BrF2- 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 Fluorine:
Fluorine is a group 17 element on the periodic table. [2]
Hence, the valence electrons present in fluorine is 7 (see below image).
Hence in a BrF2- ion,
Valence electrons given by Bromine (Br) atom = 7
Valence electrons given by each Fluorine (F) atom = 7
Electron due to -1 charge, 1 more electron is added
So, total number of Valence electrons in BrF2- 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 BrF2- ion, if we compare the bromine atom (Br) and fluorine atom (F), then the bromine is less electronegative than fluorine.
So, bromine should be placed in the center and the remaining 2 fluorine atoms will surround it.
Step #3: Put two electrons between the atoms to represent a chemical bond
Now in the above sketch of BrF2, put the two electrons (i.e electron pair) between each bromine atom and fluorine atom to represent a chemical bond between them.
These pairs of electrons present between the Bromine (Br) and Fluorine (F) atoms form a chemical bond, which bonds the bromine and fluorine atoms with each other in a BrF2 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 BrF2, the outer atoms are fluorine atoms.
So now, you have to complete the octet on these fluorine atoms (because fluorine requires 8 electrons to have a complete outer shell).
Now, you can see in the above image that all the fluorine atoms form an octet.
Also, only 16 valence electrons of BrF2- ion are used in the above structure.
But there are total 22 valence electrons in BrF2- 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.
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 fluorine atom (F).
For that, you need to remember the formula of formal charge;
Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2
- For Bromine:
Valence electron = 7 (as it is in group 17)
Nonbonding electrons = 6
Bonding electrons = 4 - For Fluorine:
Valence electron = 7 (as it is in group 17)
Nonbonding electrons = 6
Bonding electrons = 2
Formal charge | = | Valence electrons | – | Nonbonding electrons | – | (Bonding electrons)/2 | ||
Br | = | 7 | – | 6 | – | 4/2 | = | -1 |
F | = | 7 | – | 6 | – | 2/2 | = | 0 |
Let’s keep these charges on the atoms in the above lewis structure of BrF2- ion.
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 BrF2 molecule.
Hence, the above lewis structure of BrF2- ion is the stable lewis structure.
Each electron pair (:) in the lewis dot structure of BrF2- ion represents the single bond ( | ). So the above lewis dot structure of BrF2- ion can also be represented as shown below.
Related lewis structures for your practice:
Lewis Structure of P2
Lewis Structure of IBr2-
Lewis Structure of PI3
Lewis Structure of NOBr
Lewis Structure of ClF2-
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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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