So from our last lesson video, we already know that there are 2 types of covalent bonds due to the differences in atoms' electronegativities. Or in other words, due to the differences in how hard atoms pull on electrons. In this video, we're going to talk about our first type of covalent bonds which are the nonpolar covalent bonds. Nonpolar covalent bonds are, of course, a type of covalent bond, and we already know from our last lesson video that the term "Covalent" refers to the sharing of electrons between atoms. There will be sharing of electrons between atoms in nonpolar covalent bonds. The term nonpolar is a term that refers to equality, so nonpolar covalent bonds are described by equal sharing of electrons between atoms. The reason that the electrons are being shared equally in nonpolar covalent bonds is due to the equal or similar electronegativities of the atoms involved in the nonpolar covalent bond. In other words, the two atoms involved in a nonpolar covalent bond will pull on electrons equally or very similarly, and therefore they share those electrons equally.

If we take a look at our image below, we'll be able to see 3 different examples of nonpolar covalent bonds. Each person in this little interesting image represents an atom. There are 2 atoms here sharing this electron between them equally. In our first example, we have a molecule called hydrogen gas whose chemical formula is H₂, meaning that it consists of 2 hydrogen atoms. There is a line between these 2 hydrogen atoms, which represents a covalent bond. In this case, it represents a nonpolar covalent bond because these 2 identical hydrogen atoms have equal electronegativities, which means that they pull equally on this shared pair of electrons between them. Thus, those electrons will be shared equally between the 2 atoms. Equal sharing of electrons between atoms results in nonpolar covalent bonds.

The next example is a molecule called oxygen gas whose chemical formula is O₂. It consists of 2 identical oxygen atoms sharing, in this case, 2 pairs of electrons in a double bond, which is why you see two lines between those 2 oxygen atoms. These 2 covalent bonds are nonpolar covalent bonds because those 2 pairs of electrons are being shared equally between those 2 identical atoms. These 2 identical oxygen atoms have equal electronegativities and thus pull equally on those 2 shared pairs of electrons.

In our last example, unlike the first two examples where the atoms were identical, this example involves different types of atoms or different elements. We have a carbon atom and 4 hydrogen atoms; this is the molecule methane. The carbon atom is central, and the 4 hydrogen atoms are around the carbon atom, each bonded to the central carbon atom via nonpolar covalent bonds. There are 4 nonpolar covalent bonds linking each of the 4 hydrogen atoms to the carbon. These bonds are nonpolar covalent bonds because the carbon and hydrogen atoms have very similar electronegativities. They are not identical, but they are similar enough that those electrons are shared relatively equally, creating a nonpolar covalent bond.

Here we see another image depicting an electron represented as e^- in the middle of a tug-of-war match; each person represents an atom. This shows that the two people are pulling equally on the electron, symbolizing equal sharing in nonpolar covalent bonds, a key takeaway here. This concludes our brief introduction to nonpolar covalent bonds. We'll be able to get some practice as we move forward and then we'll discuss polar covalent bonds. See you all in our next video.