Now from our last lesson video, we know that there are 2 types of covalent bonds that exist due to differences in atoms' electronegativities or how hard atoms pull on electrons. And so in this video, we're going to talk about the first type of covalent bond, which is the nonpolar covalent bond. Now as we mentioned in our last lesson video, the word covalent here means sharing of electrons, and so even in nonpolar covalent bonds, there's going to be some sharing of electrons. Now the word nonpolar here is really referring to the equal sharing of electrons between atoms, and so nonpolar covalent bonds are described by equal sharing of electrons between atoms. Now the reason that the electrons are being shared equally in nonpolar covalent bonds is because the 2 atoms have similar electronegativities or they pull very similarly on the electrons.

And so if we take a look at our example image down below of nonpolar covalent bonds, what you'll see is we've got a little image here of 2 people sharing the electrons very equally. And so you can imagine that hydrogen gas, which is, molecular formula is H₂, is going to be 2 hydrogen atoms as we see right here that are forming a covalent bond and they are sharing electrons, and you can see that down below as well that, these 2 electrons right here are being shared between these 2 hydrogen atoms. Now the hydrogen atoms have identical electronegativities because they are the same atom and that means that the 2 hydrogen atoms pull exactly the same on these 2 electrons that are being shared. And so because they both pull exactly the same on those 2 electrons, they're going to share these 2 electrons really equally. And so that means that this bond that forms between these 2 hydrogens is going to be a nonpolar covalent bond, equal sharing of electrons between these atoms.

Now, very similarly, over here in the middle what we have is oxygen gas which we know its chemical formula is O₂. And so it's going to be 2 oxygen atoms, that are forming bonds between each other. And each of these lines represents the sharing of a pair of electrons and so when we take a look down below right here, notice that there are 2 pairs of electrons being shared which is why it forms this double bond right here. Whereas over here there's only 1 pair of electrons being shared so that's why it only forms a single bond, one bond. Now, the 2 oxygen atoms because they are the same element they have the exact same electronegativity which means that the 2 oxygens are pulling on those shared electrons exactly the same.

And so once again, these two pairs of electrons that are being shared between these two atoms are going to be shared equally, between the two atoms, and that's why these bonds here forming between the 2 oxygens, are going to be nonpolar covalent bonds, equal sharing of electrons between these atoms. Now, so far what we've looked at are, bonds between atoms that are identical, But nonpolar bonds can also form between bond between atoms that are not identical, for example, this image over here. So notice that we're showing you a carbon atom forming bonds with 4 hydrogen atoms. Now the thing is is that carbon and hydrogen have very similar electronegativities. They're not identical, but they're very similar, and what this means is that they're going to pull on the electrons very similarly.

And so that means that each of these, bonds that you see here which represents a pair of electrons being shared is going to be shared equally between the carbon atom and each of the hydrogen atoms. And so because once again there is equal sharing of electrons, these are going to be nonpolar covalent bonds. And the molecular formula of this molecule is CH₄, but the common name for it is methane. And so that's another classic example of nonpolar covalent bonds. Now over here on the right what we have is a little image to help remind you that nonpolar covalent bonds is due to equal sharing of electrons.

So this little symbol that you see right here is a symbol that represents electrons and so you can see that we've got 2 people or 2 atoms if you will that are sharing this electron and pulling on the electron almost like a tug of war match. And so because these two people are of the same size, they're going to pull on the electron pretty equally. They're going to pull on it about the same and so the electron is going to remain pretty much right in the middle here and they're going to be sharing the electrons equally and that is exactly what nonpolar covalent bonds, that's how they're characterized. And so now that we've introduced nonpolar covalent bonds we'll be able to get a little bit of practice in our next video and then we'll talk about polar covalent bonds. So I'll see you all in our next video.