This experiment introduces polymer chemistry through the landmark synthesis of Bakelite — the world's first fully synthetic thermosetting polymer, invented by Leo Baekeland in 1907. The reaction proceeds in three identifiable stages: electrophilic substitution of phenol by formaldehyde under acid catalysis to give hydroxymethylphenol intermediates; polycondensation of these intermediates to form the linear, thermoplastic novolac polymer with elimination of water at each step; and further cross-linking of novolac chains by excess formaldehyde to produce the three-dimensional covalent network of Bakelite. The structural reason why Bakelite cannot be remelted is fully explained — breaking the cross-links requires energies of 340–400 kJ/mol, so the material chars and decomposes before it flows. A detailed comparison of thermoplastic and thermosetting behaviour, and of novolac and Bakelite properties, is provided. The percentage yield of solid product is calculated and compared to the theoretical maximum. The experiment carries significant safety requirements: phenol is absorbed through skin causing delayed burns; formaldehyde is a probable carcinogen (IARC Group 2A); and concentrated HCl releases toxic fumes. The entire synthesis is performed in a fume cupboard with nitrile gloves and goggles.