1. All Diels-Alder reactions a. require a diene b. require a dieneophile c. are pericyclic reactions d. all of the above 2. All electrophilic aromatic substitution (EAS) reactions require a. the generation of an electrophile b. an aromatic ring attack the electrophile to form an arenium ion c. the regeneration of the aromatic ring d. all of the above 3. The gas generated in Sandmeyer reactions is a. oxygen b. nitrogen c. methane d. carbon dioxide 4. Cyclohexanol has a much higher boiling point than cyclohexene because a. cyclohexanol has induced dipole and cyclohexene has hydrogen bridge bonding b. cyclohexanol has hydrogen bridge bonding and cyclohexene has induced dipole c. cyclohexene can pack together b