Final answer:
The product of the reaction between butanoic acid and ethanol under acidic conditions is ethyl butanoate and water.
Step-by-step explanation:
The reaction of butanoic acid (C3H7COOH) and ethanol (C2H5OH) under acidic conditions typically leads to the formation of an ester and water, in a process known as esterification. The product of this particular reaction is ethyl butanoate and water (H2O). The reaction equation for this esterification is:
CH3CH2CH2COOH + C2H5OH → CH3CH2CH2COOC2H5 + H2O
Ethyl butanoate is an ester commonly used in perfumes and as a flavoring agent due to its pleasant fruity odor.