CHAPTER 5 Helpful Hints

• A rate-limiting step is the step of a multi-step reaction with transition state of highest energy. Reacting molecules must have kinetic energy equal to, or greater than, this energy in order to overcome this potential energy barried and be converted all the way to products.
• Organic reactions are generally of two flavors: The common polar reactions (pairs of electrons taking part in bond breaking, making) and the less-common radical reactions (unpaired electrons and homolytic bond breaking, making).
• Reactions are like crimes, they need motive (Delta G < 0) and opportunity (reasonable mechanism with a low or moderate activation energy).
• In general, reactions are favored (have a motive) if stronger bonds are formed than are broken (Delta H < 0), and/or more molecules are made than consumed (Delta S > 0).