Chapter 4 Learning Objectives:
  1. Be able to define:  homolytic cleavage, heterolytic cleavage, free radical, carbocation, carbanion, singlet carbene, reactive intermediate, transition state, reaction mechanism, thermodynamics, kinetics, activation energy, rate determining step (rds), Hammond Postulate, inductive effect, resonance effect.
  2. Be able to draw the six steps of a free radical chain mechanism (including curvy arrows) for the halogenation of an alkane or cycloalkane.  Label each step as an initiation step, propagation step, or termination step.
  3. Given one step of a free radical chain mechanism, be able to identify it as an initiation step, propagation step, or termination step.
  4. Be able to determine whether a reaction is endothermic or exothermic given the change in enthalpy, DH.
  5. Be able to draw an reaction-energy diagram for a given reaction step or series of steps:  include reactants, products, reactive intermediates, transition states, activation energy (DEa ), and DH on the diagram.
  6. Know how activation energy (DEa ) relates to the rate of the reaction step.
  7. Be able to use the Hammond postulate to predict whether a transition state complex will more closely resemble the reactant or the product.  Be able to draw the transition state complex based on your predictions.
  8. Be able to use a reaction-energy diagram to identify the rate-determining step for a given reaction.
  9. Be able to classify a radical as methyl, primary, secondary, or tertiary.
  10. Be able to determine relative stability of a series of radicals based on the inductive effect and the resonance effect.
  11. Be able to predict the monohalogenation organic products formed in the halogenation of an alkane and predict their relative yields.
  12. Know the hybridization of the following reactive intermediates:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  13. Be able to classify of the following reactive intermediates as electron deficient and/or electron rich:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  14. Know the geometry and the ideal bond angles of the following reactive intermediates:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  15. Be able to classify of the following reactive intermediates as nucleophilic or electrophilic:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  16. Know the net charge of the following reactive intermediates:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  17. Given a structure, be able to identify it as one the following reactive intermediates:  alkyl radicals, carbocations, carbanions, singlet carbenes.
  18. Be able to draw examples of the following reactive intermediates includiing correct geometry, charge, and orbital that are empty or that contain nonbonded electron:  alkyl radicals, carbocations, carbanions, singlet carbenes.