By the late 1920s, scientists realized that electrons cannot be precisely located around atoms. The best we can do is describe the shape of the probability volume electrons take around atoms. Linus Pauling in the 1930s then took these shapes, and used to them to describe electrons' probability shapes around whole molecules with valence bond theory, explaining why molecules have the shapes they do. We also talk about molecular orbital theory, and how it usually--but not always--agrees with hybridization theory. Patreon subscribers get a supplemental sheet with diagrams.Support the show Support my podcast at https://www.patreon.com/thehistoryofchemistry Tell me how your life relates to chemistry! E-mail me at steve@historyofchem.com Get my book, O Mg! How Chemistry Came to Be, from World Scientific Publishing, https://www.worldscientific.com/worldscibooks/10.1142/12670#t=aboutBook