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Final Review  209
463. The first step in the preparation of TNT (trinitrotoluene) is the 
mononitration of toluene. (The toluene undergoes two additional 
nitrations to yield the final product.) The first step in the formation 
of TNT is:
CH3
HNO3/H2SO4
CH3
O2N
What is the most likely position for the NO2 relative to the CH3?
(A) Ortho or para
(B) Ortho or meta
(C) Meta or para
(D) Meta only
464. The melting points for the nitrobenzoic acids are in the following table:
Ortho-nitrobenzoic acid 147°C
Meta-nitrobenzoic acid 140°C
Para-nitrobenzoic acid 242°C
Why is the melting point of para-nitrobenzoic acid so much higher than 
that of either of the other two compounds in the table?
(A) Para-nitrobenzoic acid has intermolecular hydrogen bonding, and the 
other two have intramolecular hydrogen bonding.
(B) Para-nitrobenzoic acid has intramolecular hydrogen bonding, and the 
other two have intermolecular hydrogen bonding.
(C) Only para-nitrobenzoic acid can participate in hydrogen bonding.
(D) Para-nitrobenzoic acid undergoes an acid-base reaction with the 
neighboring molecules to form a covalent bond between the molecules.
465. The mononitration of phenol yields a mixture of ortho-nitrophenol and 
para-nitrophenol. Ideally, what will be the melting point of a mixture 
containing equal amounts of these two isomers?
(A) Below the melting point of the lower-melting compound
(B) Above the melting point of the higher-melting compound
(C) The average of the two melting points
(D) Slightly above the average of the two melting points