Preparation of acetanilide, p-nitroacetanilide and aspirin — practice questions

Question 1 · difficulty L1 · recall

Acetanilide is commonly prepared in the laboratory by acetylation of which compound?

• A. Phenol
• B. Aniline
• C. Benzoic acid
• D. Benzaldehyde

Question 2 · difficulty L1 · recall

Aspirin is formed when salicylic acid is acetylated. Which group of salicylic acid is acetylated in the product?

• A. The phenolic hydroxyl group
• B. The aromatic ring is completely hydrogenated
• C. The carboxyl carbon is removed as carbon dioxide
• D. The benzene ring is cleaved into two fragments

Question 3 · difficulty L2 · understanding

Why is aniline often converted to acetanilide before carrying out controlled nitration?

• A. The acetamide group becomes a meta-directing nitro group
• B. Acetylation removes the benzene ring before nitration
• C. It moderates amino-group activation during nitration
• D. Acetanilide cannot undergo electrophilic substitution

Question 4 · difficulty L3 · application

In the preparation of p-nitroacetanilide from acetanilide, which reaction introduces the nitro group?

• A. Hydrolysis of the acetamide group
• B. Nucleophilic substitution at the carbonyl carbon
• C. Free-radical addition across a double bond
• D. Electrophilic aromatic nitration

Question 5 · difficulty L5 · analysis

A crude sample of acetanilide contains a small amount of soluble impurity. Which purification strategy best exploits the usual temperature dependence of solubility?

• A. Wash the dry solid repeatedly with large volumes of hot solvent
• B. Recrystallise from minimum hot solvent and cool
• C. Evaporate the sample to dryness without dissolving it
• D. Add an insoluble powder so that every component precipitates together