Hydrolysis reactions producing specific carboxylic acids Steps:

• Identify structures: propyl ethanoate (CH₃COOC₃H₇), ethyl ethanoate (CH₃COOC₂H₅), propanenitrile (CH₃CH₂CN), ethanenitrile (CH₃CN).
• Recall products: alkaline ester hydrolysis gives carboxylate salt; acid ester/nitrile hydrolysis gives carboxylic acid.
• Check A: alkaline hydrolysis yields CH₃COO⁻ (ethanoate salt).
• Check B, C, D: acid hydrolysis yields CH₃COOH (ethanoic acid) for B and D; CH₃CH₂COOH (propanoic acid) for C.

Why C is correct:

• Acid hydrolysis of nitriles follows RCN + 2H₂O + HCl → RCOOH + NH₄Cl; for propanenitrile (R = CH₃CH₂), it yields propanoic acid.

Why the others are wrong:

• A: Alkaline hydrolysis of propyl ethanoate gives sodium ethanoate (CH₃COONa), requiring acidification for the acid.
• B: Acid hydrolysis of ethyl ethanoate gives ethanoic acid (CH₃COOH).
• D: Acid hydrolysis of ethanenitrile gives ethanoic acid (CH₃COOH).

Final answer: C