CH4 (Methane) is a covalent (nonpolar covalent) compound because when one nonmetal combines with another nonmetal, it usually forms a covalent compound. Here, C is a nonmetal and H is also a nonmetal. So when they combine, it forms a covalent compound.
Well, now you have got to know that CH4 is a covalent compound, but let me explain the in-depth reason why CH4 is a covalent compound.
If you are a visual learner like me, then here is a short one minute video for you.
Why is CH4 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 CH4, the C atom is a nonmetal and the H atom is also a nonmetal.
Hence the bond between them is a covalent bond.
How does the covalent bond form in CH4?
In CH4, there are two atoms;
C and H.
About Carbon (C):
Carbon atom have 6 electrons.
The electrons arrangement in Carbon (C) is 2, 4.
So the outermost orbit of Carbon atom has 4 electrons.
Now in order to achieve a stable octet, the Carbon atom needs 4 more electrons.
Hence during the chemical reaction, the Carbon atom will gain 4 electrons from the combining atom to form a stable octet.
About Hydrogen (H):
Hydrogen atom have 1 electron.
It has only 1 orbit and there is only 1 electron in this orbit.
Now in order to achieve a stable duplet, the Hydrogen atom needs 1 more electron.
Hence during the chemical reaction, the Hydrogen atom will gain 1 electron from the combining atom to form a stable duplet.
What happens when C and H combine?
When C and H combine with each other, the Carbon atom and Hydrogen atoms mutually share their 1-1 electrons with each other.
Because of this the carbon atom will have 8 electrons in its outermost orbit and similarly the hydrogen atom will also have 2 electrons in its outermost orbit.
As a result, the carbon atom and hydrogen atoms will have a stable octet and duplet respectively.
And finally, as the bond formed between the carbon and hydrogen is due to the mutual sharing of electrons, it is considered a covalent bond.
Thus, CH4 is a covalent compound.
Is CH4 polar covalent or nonpolar covalent?
In order to know whether CH4 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 Carbon and Hydrogen are mentioned below. (You can see the electronegativity of all the elements from this electronegativity chart).
- Electronegativity of Carbon (C) = 2.55
- Electronegativity of Hydrogen (H) = 2.2
So for CH4, the electronegativity difference (ΔEN) = 2.55 – 2.2 = 0.35
This value is less than 0.4, which indicates that the bond between the Carbon (C) atom and Hydrogen atom (H) is nonpolar covalent bond.
Also if you look at the 3D structure of CH4, you can see that the structure of CH4 is symmetrical.
Hence, CH4 (methane) is a nonpolar covalent molecule.
I hope you have understood the reason why CH4 is a nonpolar covalent compound.
Check out other compounds to see whether they are ionic or covalent;
Is MgCl2 (Magnesium chloride) Ionic or Covalent?
Is SO2 (Sulfur dioxide) Ionic or Covalent?
Is MgO (Magnesium oxide) Ionic or Covalent?
Is CCl4 (Carbon tetrachloride) Ionic or Covalent?
Is CaO Ionic or Covalent?
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.
Read more about our Editorial process.