Unit 3: Bonding
Bonds are connections between atoms. (Note that although we will focus on bonds in this unit, there are additional forces that affect atoms, i.e., intermolecular forces.) A solid grasp of VSEPR (Valence Shell Electron Pair Repulsion) theory will help us understand how elements that differ by one or two atomic numbers behave similarly or differently. VSEPR theory explains that the number of electrons an element possesses is intimately tied to its chemical properties. For example, though sodium differs from both neon and potassium by just one atomic number, it is extremely different from neon but very similar to potassium. This is because neon is a stable element with eight valence electrons (as predicted by VSEPR theory). Sodium and potassium have one and two valence electrons, respectively, which explain why they are similar to one another but quite different from neon. VSEPR is also used to predict the 3-dimensional structure, or geometry, of molecules.
Completing this unit should take you approximately 17 hours.