Final answer:
The product of the reaction between acetophenone and 2,4-dinitrophenylhydrazine is the 2,4-dinitrophenylhydrazone of acetophenone, which involves the formation of a hydrazone linkage.
Step-by-step explanation:
The structural formula for the product of the reaction between acetophenone and 2,4-dinitrophenylhydrazine, under acid catalysis, is a hydrazone. Specifically, it is 2,4-dinitrophenylhydrazone of acetophenone. To draw this structure, we connect the nitrogen of the 2,4-dinitrophenylhydrazine to the carbon of the carbonyl group (C=O) of acetophenone, replacing the oxygen. This process involves the nucleophilic addition of the hydrazine to the carbonyl carbon, followed by the elimination of water.