UESTION 9 Cyclopentadiene is unusually acidic for a hydrocarbon (i.e., it loses hydrogen easily to a base). Why? O Cyclopentadiene is aromatic. Removal of a hydride ion (H:") from cyclopentadiene yields an aromatic cation. Removal of H* from cyclopentadiene yields an aromatic anion. Removal of a hydrogen atom from cyclopentadiene yields an aromatic radical. QUESTION 10 Which reagent will react with benzene?

Substituents on an aromatic ring can have several effects on electrophilic aromatic substitution reactions. Substituents can activate or deactivate the ring to substitution, donate or withdraw electrons inductively, donate or withdraw electrons through resonance, and direct substitution either to the ortho/para or to the meta positions. From the lists of substituents, select the substituents that correspond to each indicated property. The substituents are written as -XY, where X is the atom directly bound to the aromatic ring.

Rank the following groups in order of their ability to activate an aromatic compound to electrophilic aromatic substitution.

Rank these alkyl halides in order of increasing reactivity in an SN2 reaction