NF3 is a covalent (polar covalent) compound because when one nonmetal combines with another nonmetal, it usually forms a covalent compound. Here, N is a nonmetal and F is also a nonmetal. So when they combine, it forms a covalent compound.
Well, now you have got to know that NF3 is a covalent compound, but let me explain the in-depth reason why NF3 is a covalent compound.
If you are a visual learner like me, then here is a short one minute video for you.
Why is NF3 a Covalent compound?
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 NF3, the N atom is a nonmetal and the F atom is also a nonmetal.
Hence the bond between them is a covalent bond.
How does the covalent bond form between N and F?
In NF3, there are two atoms;
N and F.
About Nitrogen (N):
Nitrogen atom have 7 electrons.
The electrons arrangement in Nitrogen (N) is 2, 5.
So the outermost orbit of Nitrogen atom has 5 electrons.
Now in order to achieve a stable octet, the Nitrogen atom needs 3 more electrons.
Hence during the chemical reaction, the Nitrogen atom will gain 3 electrons from the combining atom to form a stable octet.
About Fluorine (F):
Fluorine atom have 9 electrons.
The electrons arrangement in Fluorine (F) is 2, 7.
So the outermost orbit of Fluorine atom has 7 electrons.
Now in order to achieve a stable octet, the Fluorine atom needs 1 more electron.
Hence during the chemical reaction, the Fluorine atom will gain 1 electron from the combining atom to form a stable octet.
What happens when N and F combine?
When N and F combine with each other, the Nitrogen atom and Fluorine atoms mutually share their 1-1 electrons with each other.
Because of this the nitrogen atom will have 8 electrons in its outermost orbit and similarly the fluorine atom will also have 8 electrons in its outermost orbit.
As a result, the nitrogen as well as fluorine atom will have a stable octet.
And finally, as the bond formed between the nitrogen and fluorine is due to the mutual sharing of electrons, it is considered a covalent bond.
Thus, NF3 is a covalent compound.
Is NF3 polar covalent or nonpolar covalent?
In order to know whether NF3 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 Nitrogen and Fluorine are mentioned below. (You can see the electronegativity of all the elements from this electronegativity chart).
- Electronegativity of Nitrogen (N) = 3.04
- Electronegativity of Fluorine (F) = 3.98
So for NF3, the electronegativity difference (ΔEN) = 3.98 – 3.04 = 0.94
This value lies between 0.4 to 1.7, which indicates that the bond between Nitrogen (N) and Fluorine (F) is polar covalent bond.
But the NF3 molecule has 1 lone pair which results in an asymmetric shape of the entire NF3 molecule.
Because of this asymmetric shape there are positive and negative poles of charges on the overall molecule of NF3.
Hence, NF3 is a polar covalent molecule.
I hope you have understood the reason why NF3 is a polar 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 learning platform that provides students with easily understandable explanations.
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