Unit 9: Aromatic Hydrocarbons

31. Which reaction is used to introduce a carbonyl group into an aromatic ring?

a) Friedel-Crafts alkylation
b) Friedel-Crafts acylation
c) Nitration
d) Sulfonation
Answer: b) Friedel-Crafts acylation

32. The reduction of nitrobenzene yields:

a) Aniline
b) Phenol
c) Benzyl alcohol
d) Benzene
Answer: a) Aniline

33. The product of the reaction of benzene with sulfur trioxide in the presence of a catalyst is:

a) Benzene sulfonic acid
b) Benzyl alcohol
c) Phenyl sulfide
d) Benzyl chloride
Answer: a) Benzene sulfonic acid

34. Which aromatic compound is used in the synthesis of dyes and drugs?

a) Benzene
b) Toluene
c) Aniline
d) Phenol
Answer: c) Aniline

35. In the Friedel-Crafts reaction, the role of the Lewis acid catalyst is to:

a) Donate electrons
b) Accept electrons
c) Protonate the substrate
d) Deprotonate the substrate
Answer: b) Accept electrons

36. Which aromatic hydrocarbon is used as a solvent in the paint industry?

a) Toluene
b) Xylene
c) Benzene
d) All of the above
Answer: d) All of the above

37. The presence of a nitro group on an aromatic ring usually:

a) Increases electron density on the ring
b) Decreases electron density on the ring
c) Has no effect on electron density
d) Converts the ring to a non-aromatic structure
Answer: b) Decreases electron density on the ring

38. The main use of benzene in industry is as a precursor for the synthesis of:

a) Pharmaceuticals
b) Synthetic fibers
c) Dyes
d) All of the above
Answer: d) All of the above

39. Aniline is commonly used in the production of:

a) Rubber
b) Pesticides
c) Plastics
d) Pharmaceuticals
Answer: d) Pharmaceuticals

40. In the reaction of phenol with formaldehyde, the product is:

a) Phenol formaldehyde resin
b) Benzyl alcohol
c) Benzene
d) Phenylhydrazine
Answer: a) Phenol formaldehyde resin