1. Gas Properties & Behavior | Relationship between gas properties, molecular structure, pressure, and diffusion. 2. Atomic Structure & Ions | Electron configuration, isotopes, nucleon numbers, and charge determination. 3. Chemical Reactions & Bonding | Covalent bonding, empirical formulas, reaction types, and exothermic vs. endothermic processes. 4. Stoichiometry & Chemical Calculations | Mole concept, mass calculations, and reaction rates under different conditions. 5. Electrolysis & Redox Reactions | Electrolytic changes, oxidation states, and effects of catalysts. 6. Organic Chemistry & Hydrocarbons | Alkanes, alkenes, combustion, functional groups, and reaction mechanisms.