Hello everybody and in this video we're going to continue talking about chemical bonding. We've already learned about two types of chemical bonding. Now we're going to learn about the third. We'll discuss cobalan bonding in the types of bonds that can be found in a cobalan compound. Let's quickly review what we've already seen in terms of bonding. We've already discussed psionic bonding which is the transfer of electrons between a metal and a non-metal. Here is metallic bonding which is the attraction of metal ions that creates the sea of electrons. What we're going to focus on in this video is covalent bonding. And in covalent bonding we're going to see a sharing of electrons between two non-metal elements and this will allow for something called polar or non-polar covalent compounds to form. It's important that we keep in mind that all bonding occurs so that every atom will have eight electrons in its outer valent shell. Covalent bonding is the sharing of electrons between non-metal elements. These elements are found on the right side of the periodic table plus hydrogen. The example here shows water H2O and you'll notice as high the two hydrogens move in towards the oxygen to react they're going to end up having a sharing of electrons between hydrogens and oxygens. This creates what is called a molecule. And the molecule is a neutral group of atoms that are held together by covalent bonds. Carbon dioxide which is CO2 water they are all considered molecules. A molecular formula will show the types and numbers of atoms in a covalent bonded compound. Here with C6H1206 we can see that we have 6 carbon atoms, 12 hydrogen atoms and we'll have 6 oxygen atoms that will bond to form that compound. Apollietomic is a charged group of covalent bonded atoms. We will discuss these in a little bit more detail later but you'll notice that carbon is a non-metal oxygen is a non-metal so they are covalently bonded but the overall group will have this charge of a minus 2 on it. Diatomics are atoms that cannot exist alone must be paired. There are 7 diatomics, hydrogen, nitrogen, oxygen and the halogens which is fluorine, chlorine, bromine and iodine. You will not see hydrogen written as just an H. It will be written as H2 and that goes for the other 6. I'll show you a neat way of remembering this in class. Something unique with covalent bonds is that they can create different types of bonds. There are three different bonds that can occur with covalent bonding. A single bond, a double bond and a triple bond and just like their names, you could pretty much figure out what's happening between the elements. In a single bond there's one pair of electrons shared, double bond, there's two pairs and a triple bond, there's three pairs. With the sharing of electrons it's going to affect the strength and the length of these particular bonds. So hydrogen had one bond between it, oxygen had two and nitrogen had three from the previous slide. If you think about it, hydrogen has only two electrons shared between the two. Nitrogen has six. When you look at this it's going to be easier to break apart the hydrogen instead of breaking apart the nitrogen. So it makes the triple bond stronger. So this is stronger. It's really the strongest out of the three. That strongest bond also is the shortest because there are six electrons here that are shared. They're pulling the nitrogen closer together. So this is the shortest. So it's important for you to be able to remember that. That ends the first video on covalent bonds. Our next video we'll talk about drawing the Lewis structure for covalent compounds. So please make sure that you write down the sample problems and follow along as we go through those notes.