(1) Groups 13–15 of the p-block are distinguished by their valence electron configurations $ns^{2}$ $np^{1}$, $ns^{2}$ $np^{2}$, and $ns^{2}$ $np^{3}$ respectively, which determine their dominant oxidation states and bonding patterns. (2) Boron is anomalous in Group 13 — it forms only covalent, electron-deficient compounds and acts as a Lewis acid, as exemplified by diborane ($B_{2}H_{6}$) with its unique 3-centre-2-electron banana bonds. (3) Boric acid ($H_{3}BO_{3}$) is a monobasic Lewis acid that accepts $OH^{-}$ from water rather than donating $H^{+}$, making it chemically distinct from Bronsted acids. (4) $AlCl_{3}$ dimerises to $Al_{2}Cl_{6}$ due to the electron deficiency of Al and is a crucial Friedel-Crafts Lewis acid catalyst. (5) Carbon in Group 14 exhibits three major allotropes — diamond ($sp^{3}$, hardest, insulator), graphite ($sp^{2}$, conductor, lubricant), and fullerene ($C_{60}$, spherical cage) — illustrating how structure dictates macroscopic properties. (6) The Haber process synthesises ammonia from $N_{2}$ and $H_{2}$ using an iron catalyst at 450°C and 200 atm, chosen as a compromise between reaction rate and equilibrium yield. (7) The Ostwald process converts $NH_{3}$ to $HNO_{3}$ in three sequential steps using Pt/Rh catalyst only in Step 1 (500°C). (8) Nitrogen oxides range from neutral $N_{2}$O (+1) and NO (+2) through acidic N_{2}$$O_{3} (+3), $NO_{2}$ (+4), and N_{2}$$O_{5} (+5), with only NO and $NO_{2}$ being paramagnetic. (9) $PCl_{5}$ adopts a trigonal bipyramidal geometry ($sp^{3}$d), with axial bonds longer than equatorial bonds due to greater repulsion; $NCl_{5}$ cannot exist as N lacks d-orbitals. (10) The basicity of phosphorus oxoacids is determined solely by P-OH bond count: $H_{3}PO_{2}$ is monobasic (1), H_{3}P$$O_{3} is dibasic (2), and H_{3}P$$O_{4} is tribasic (3) — never by total hydrogen count.