Final answer:
The correct carboxylic acid needed to form isobutyl benzoate is acetic acid (option a).
Step-by-step explanation:
Answer:
The correct carboxylic acid needed to form isobutyl benzoate is acetic acid (option a).
Isobutyl benzoate is an ester formed from the reaction between benzoic acid and isobutanol. The reaction is a condensation reaction where water is produced as a byproduct:
Benzoic acid + Isobutanol --> Isobutyl benzoate + Water
Acetic acid, being part of the same carboxylic acid family as benzoic acid, would also be capable of undergoing this esterification reaction to form isobutyl benzoate.