CONCHEM 2ND LESSON

• Addition Reaction (A+B 🠖 C) is the addition of an atom or a group of atoms to the adjacent carbons of a multiple bond without the removal of atoms or other molecules.
• Hydrogenation (H-H addition) is the addition of hydrogen to the multiple bonds, in the presence of a catalyst (Pt, Pd, Rh or Ni).
• Halogenation (X addition) is the addition of halogens, forming a vicinal halide (a compound that contains a halogen atom on adjacent carbons).
• Vicinal halide is a compound containing a halogen atom on adjacent carbons.
• Hydrohalogenation (H-X addition) is the addition of gaseous hydrogen halide, HX, forming an alkyl halide.
• HI > HBr > HCl.
• Hydration (H-OH addition) is the addition of water to the carbon-carbon multiple bonds to yield an alcohol.
• An acid catalyst must be present during hydration.
• Hydrogenation follows Markovnikov’s rule.
• Markovnikov’s Rule states that when a hydrogen halide adds to an unsymmetrical alkene/alkyne, the hydrogen adds to the carbon that already holds the greater number of hydrogens and the halogen adds to carbon with fewer hydrogens.
• Anti-Markovnikov’s Rule, also called as Kharasch addition or peroxide effect, is promoted when peroxides were present during the reaction of HBr addition.
• Elimination Reaction is the intramolecular loss or removal of an atom or group of atoms from adjacent carbon atoms, resulting in the formation of a multiple bond.
• Dehydrogenation (H-H elimination) is the removal of hydrogen.
• Dehalogenation (X - elimination) is the removal of halogens.
• Dehydrohalogenation (H-X elimination) is the removal of hydrogen and halogen.
• Dehydration (H-OH elimination) is the removal of water.
• Polymerization is the combining together of a single unit of molecules (monomers) to form one large molecule called polymer.
• Addition Polymerization (Chain Reaction) is a polymer that forms by simple linking of monomers without the co-generation of other products.
• Condensation Polymerization (Step-Reaction) is a form of step-growth polymerization in which monomers and/or oligomers react with each other to form larger structural units while releasing smaller molecules as a byproduct such as water or methanol.