Atomic Structure and Properties

Atomic structure is not background information; it is the first half of the course's core argument. Where an electron sits in an atom determines how that atom bonds, and how it bonds determines everything that follows: geometry, polarity, intermolecular forces, reactivity. Electron configuration is not a memorization task; it is a set of rules that explains why sodium loses one electron willingly and why chlorine takes it. Photoelectron spectroscopy gives you experimental evidence for shell structure, so you can see that the model is not invented. Periodic trends are the payoff; once you understand why ionization energy increases across a period, you stop memorizing and start predicting.

7–9% of exam