Nonpolar Covalent Chemical Bonds
In chemistry, we come across what we can call covalent bonds. These covalent bonds are formed when one or more pairs of electrons are shared between atoms, so the key word here is shared.
Now we can take that a step further and we have something called non-polar covalent bonds, so a couple of blanks to fill in on this definition.
The next lesson for you: Metallic Bonds; these lessons are included in the Math practice tests.The following transcript is provided for your convenience.
Two atoms with equal electronegativity that share the electron pairs equally, so that’s what non-polar covalent bonds are two atoms with equal electronegativity that share the electron pairs equally. The key words here are equal and equally, so they have to have equal electronegativity and that means they share these electrons equally. Now, the opposite of this would be polar covalent bonds, which don’t share the electron pairs equally.
In other words, the electrons spend more time with one atom over the other. We have this general definition of covenant bonds, which just means they share atoms, but it doesn’t describe how they share them, so we have non-polar and polar, but the key definition here is non-polar covalent bonds, you do share the electron pairs equally.
Now there’s one more definition I can give you and that’s the definition of the octet rule, which is: outer most shells must contain eight electrons to be complete, so the key word there is eight. Say for example we have oxygen and oxygen has seven electrons, so we have two oxygens here and these dots represent an electron, so they each have seven. But according to the octet rules, the outer shells must contain eight electrons to be complete, so what they can do here is become covalent bonds, meaning that they’re sharing electrons pairs equally.
All these electrons around the outside are their own electrons, but this electron pair right here in the middle is being shared equally between the two oxygens to become diatomic oxygen. Now there is an exception to the octet rule and that is with hydrogen and helium. These only need two electrons and so say we had hydrogen, it has one electron and we have another hydrogen with one electron, they can come together and they can share that electron pair equally between them and now they have all the electrons that they need.
The way non-polar covalent bonds usually come about is when two nonmetals chemically bond together and so what these atoms are trying to do is have a complete outer shell of eight electrons. What we have here now is two hydrogen atoms and over here we have two oxygen atoms, so we have diatomic hydrogen and diatomic oxygen. These are exhibiting non-polar bonds because the atoms have equal electro negativities.
Sometimes you may be dealing with two atoms that are of different elements, but here since the atoms are the same elements, you know they’re going to have equal electro negativities, because of the same type of atom and because they have those equal negativities, they’re able to share those electron pairs equally as well.
The next lesson for you: Metallic Bonds; these lessons are included in the Math practice tests.