Br2 is a covalent (nonpolar covalent) molecule because when one nonmetal combines with another nonmetal, it usually forms a covalent molecule (or compound). Here, both the atoms (Br) are nonmetals. So when they combine, it forms a covalent molecule.
Well, now you have got to know that Br2 is a covalent molecule, but let me explain the in-depth reason why Br2 is a covalent molecule.
If you are a visual learner like me, then here is a short one minute video for you.
Why is Br2 a Covalent molecule?
As mentioned above, you can simply remember that when the nonmetal combines with another nonmetal, the bond between them is a covalent bond.
Here in Br2, both the atoms are nonmetals.
Hence the bond between them is a covalent bond.
How does the covalent bond form in Br2?
In Br2, there are two Bromine atoms;
About Bromine (Br):
Bromine atom have 35 electrons.
The electrons arrangement in Bromine (Br) is 2, 8, 18, 7.
So the outermost orbit of Bromine atom has 7 electrons.
Now in order to achieve a stable octet, the Bromine atom needs 1 more electron.
Hence during the chemical reaction, the Bromine atom will gain 1 electron from the combining atom to form a stable octet.
What happens when Br and Br combine?
When Br and Br combine with each other, both the Bromine atoms mutually share their 1-1 electrons with each other.
Because of this, both the Bromine atoms will have 8 electrons in their outermost orbit.
As a result, both the bromine atoms will have a stable octet.
And finally, as the bond formed between the bromine atoms is due to the mutual sharing of electrons, it is considered a covalent bond.
Thus, Br2 is a covalent molecule.
Is Br2 polar covalent or nonpolar covalent?
In order to know whether Br2 is a polar covalent molecule or nonpolar covalent molecule, we have to check the electronegativity difference of the combining atoms.
If the electronegativity difference (ΔEN) is less than 0.4, then the bond is nonpolar covalent bond.
Now the electronegativity of Bromine = 2.96.
So for Br2, the electronegativity difference (ΔEN) = 2.96 – 2.96 = 0
This value is less than 0.4, which indicates that the bond between both the Bromine (Br) atoms is nonpolar covalent bond.
Hence, Br2 is a nonpolar covalent molecule.
I hope you have understood the reason why Br2 is a nonpolar covalent compound.
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 chemistry learning platform that provides students with easily understandable explanations.
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