About this video
In a metallic bond, metal atoms such as iron each give up valence electrons to a shared 'sea of electrons', leaving positive ions that are attracted to that sea. Because the electrons can move freely, metals conduct electricity and are malleable. The video ends by placing ionic, polar covalent, covalent and metallic bonds on a spectrum of electron sharing.
You'll be able to
- describe a metallic bond as positive metal ions in a sea of shared electrons.
- explain why metals conduct electricity and can bend without breaking.
- place ionic, polar covalent, covalent and metallic bonds on a spectrum of electron sharing.
Key words
- metallic bond
- The attraction between positive metal ions and a shared sea of electrons that move between them.
- sea of electrons
- The pool of valence electrons in a metal that are not fixed to any one atom and can move around.
- ion
- An atom that has gained or lost electrons, so it carries a charge, like Fe+.
- valence electrons
- The outermost electrons of an atom, the ones involved in bonding.
- malleable
- Able to be bent or shaped without breaking.
Transcript
- [Instructor] Now the last type of bond I'm going to talk about is known as the metallic bond, which I think I know a little bit about because I was the lead singer of a metallic bond in high school. I'll talk about that in future videos. But let's just take one of our metallic atoms here.
Iron is a good example. Iron is maybe one of the most referred to metals. Let's say we have a bunch of iron atoms. So Fe, Fe, Fe, Fe, hope you can read that. These are all iron atoms. And if they're just atoms by themselves they're going to be neutral. But when they are mushed together, they will form a metallic bond.
Makes sense because they're metals. And what's interesting about metallic bonds, I'll draw it down here, is that metals like to share their electrons with the other metals. It kinda forms this sea of electrons. So what it can look like is, each of the irons lose an electron, I'll draw it a little bit bigger.
So let's say this is Fe plus, so it has a positive charge. Fe plus has a positive charge. Fe plus, these are all iron ions, you can imagine. Fe plus, and we're imagining that they have this positive charge because they've all contributed an electron to this sea of electrons.
So you have an electron here which has a negative charge. And electrons are not this big, but this is just so that you can see it. Electron here that has a negative charge. And so you can imagine these positive ions are attracted to the sea of negativity, the sea of negative electrons.
Another way to think about it is, is that metals, when they bond in metallic bonds, they will have overlapping valence electrons. And those valence electrons are not fixed to just one of the atoms, they can move around. And this is what gives metals many of the characteristics we associate with metals.
It conducts electricity because these electrons can move around quite easily. It makes them malleable, you can bend it easily. You can imagine these iron ions in this pudding, or this sea of electrons. So you can bend it, it doesn't break. Well if you were to take a bar of a salt right over here, if you were to try to bend it, it's very rigid.
It is going to break. So there we have it, the types of bonds. It's important to realize that you can view it as something of a spectrum. At one end, you have things like ionic bonds where one character swipes an electron from another character and says, "Hey, but now we're attracted to each other," and you get something like salt.
Or you have covalent bonds where we outright share electrons. And then you have things in between covalent bonds and ionic bonds where the sharing is not so equal and you get polar covalent bonds. And then another form, I guess you could say, of extreme sharing is the metallic bonds where you just have this communal sea of electrons.
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