Organic Chemistry 9th Edition By Francis Carey -Test Bank
7. How many isomeric tribromobenzenes are possible?
A) one B) two C) three D) four
8. Which of the following is not true concerning the structure of benzene?
A) All C-C-C bond angles are exactly 120o
B) The carbon-carbon bonds rapidly alternate between single and double bonds.
C) The six hydrogens are equivalent.
D) The π bonds are completely conjugated.
10. The total number of resonance forms of the cyclopentadienide anion, C5H5¯ , is
A) two. B) three. C) four. D) five.
14. Which of the following reacts at the fastest rate when heated with N-bromosuccinimide
(NBS) and benzoyl peroxide in carbon tetrachloride at 80oC?
A) toluene C) isopropylbenzene (cumene)
B) ethylbenzene D) tert-butylbenzene
15. The Birch reduction of benzene with sodium in NH3/CH3OH goes by a four-step
mechanism. The first step is the
A) transfer of a proton from CH3OH to benzene.
B) transfer of an electron from Na to benzene.
C) transfer of an electron from benzene to NH3.
D) transfer of a hydride ion, H¯ , from NH3 to benzene.
18. Side chain oxidations of alkylbenzenes with Na2Cr2O7 and H2SO4/H2O will not work if
the alkyl side chain has
A) only one carbon. C) benzylic hydrogens.
B) four or more carbons. D) no benzylic hydrogens.
19. Which of the following are consistent with the requirements for aromaticity?
I. A system with delocalized π electrons in a ring.
II. 4n π electrons in the ring.
III. All the ring atoms must be carbons.
IV. (4n + 2) π electrons in the ring.
A) I and II B) I and IV C) I, II, and III D) I, III, and IV
20. Cyclopentadiene is unusually acidic for a hydrocarbon. Why?
A) Cyclopentadiene is aromatic.
B) The conjugate base of cyclopentadiene is aromatic.
C) Cyclopentadiene is an unstable diradical.
D) The conjugate base of cyclopentadiene is an unstable diradical.
27. A compound X, C8H10, is oxidized to benzoic acid with potassium dichromate, K2Cr2O7,
in sulfuric acid. What is compound X?
A) para-xylene B) propylbenzene C) styrene D) ethylbenzene
28. Acid-catalyzed dehydration of cis-2-phenylcyclopentanol gives
A) 1-phenylcyclopentene. C) 4-phenylcyclopentene.
B) phenylcyclopentane. D) 1-phenylcyclopentanol.
31. Select the best method to convert styrene, C6H5CH=CH2, to 2-phenylethanol with
minimal by-product formation.
A) H2O, H2SO4
B) (1) BH3-THF (2) H2O2, NaOH
C) (1) HBr (2) KOH, H2O
D) (1) HBr, peroxides (2) NaOH, H2O
32. Which of the following would be a correct number of π electrons for a planar,
monocyclic, completely conjugated polyene to be aromatic?
A) 3 B) 8 C) 18 D) 24