Lessons in this chapter
- 1Why Elements Are ClassifiedDiscover how recurring properties turned a growing list of elements into a system that could predict new discoveries.
- 2The Modern Periodic Table and Element NamesRead the modern table using atomic number, periods, groups, and systematic element names.
- 3How Electron Configurations Build Periods and GroupsExplain the shape of the table by following electrons into shells and subshells.
- 4Element Blocks, Metals, and Non-metalsUse electron configurations and physical properties to recognise the major kinds of elements.
- 5Atomic and Ionic SizeExplain size trends by balancing nuclear attraction, shielding, shell number, and electron repulsion.
- 6Ionization Enthalpy and Electron RemovalUnderstand the energy needed to remove electrons and the exceptions that reveal how orbitals are occupied.
- 7Electron Gain Enthalpy and ElectronegativityDistinguish electron attachment to an isolated atom from electron attraction inside a bond.
- 8Valence, Oxidation States, and Second-Period ExceptionsUse outer electrons to predict combining patterns, then explain where the simplest patterns need refinement.
- 9Periodicity, Reactivity, and OxidesConnect atomic properties to chemical reactions, natural occurrence, and the acid–base behaviour of oxides.
- 10Chapter Summary and PracticeConnect the whole chapter and practise choosing explanations rather than memorising isolated trend arrows.