d-Block Elements — Transition Metals

d-Block transition elements at PGT depth: definition and general properties (variable oxidation states, colour, magnetism, catalysis), the four series (3d, 4d, 5d, 6d), inner transition (lanthanides/actinides preview), and important compounds (KMnO₄, K₂Cr₂O₇, ferrous/ferric, copper compounds).