Videos: Chemical Bonds

Atomic Hook-Ups—Types of Chemical Bonds: Crash Course Chemistry #22

Atoms are a lot like us—we call their relationships “bonds,” and there are many different types. Each kind of atomic relationship requires a different type of energy, but they all do best when they settle into the lowest stress situation possible. The nature of the bond between atoms is related to the distance between them and, like people, it also depends on how positive or negative they are. Unlike with human relationships, we can analyze exactly what makes chemical relationships work, and that’s what this episode is all about.

If you are paying attention, you will learn that chemical bonds form in order to minimize the energy difference between two atoms or ions; that those chemical bonds may be covalent if atoms share electrons, and that covalent bonds can share those electrons evenly or unevenly; that bonds can also be ionic if the electrons are transferred instead of shared: and how to calculate the energy transferred in an ionic bond using Coulomb’s Law.

Polar & Non-Polar Molecules: Crash Course Chemistry #23

Molecules come in infinite varieties, so in order to help the complicated chemical world make a little more sense, we classify and categorize them. One of the most important of those classifications is whether a molecule is polar or non-polar, which describes a kind of symmetry – not just of the molecule, but of the charge. In this edition of Crash Course Chemistry, Hank comes out for Team Polar, and describes why these molecules are so interesting to him.

You’ll learn that molecules need to have both charge asymmetry and geometric asymmetry to be polar, and that charge asymmetry is caused by a difference in electronegativities. You’ll also learn how to notate a dipole moment (or charge separation) of a molecule, the physical mechanism behind like dissolves like, and why water is so dang good at fostering life on Earth.

Please watch with the annotations on! Some inaccuracies in graphics are noted and corrected in annotations. Thanks!