Periodic table organization and trends (radius, IE, EN, reactivity)
Foundations of chemistry for beginners: atomic structure, isotopes and ions, periodic table groups/periods, key periodic trends, and the octet rule (including common exceptions).
Beginner-friendly Pre-med/IB-style questions on periodic table group properties (Group 1, 2, 17, 18), how groups react with each other (especially metals + halogens, halogen displacement), and using the metal reactivity series to predict reactions, extraction, and corrosion protection.
High-school/pre-med-beginner practice on periodic trends with conceptual traps: atomic/ionic radius, effective nuclear charge, shielding, first ionization energy (including common exceptions), electron affinity, electronegativity, and metallic character. Emphasis on reasoning, not memorization.