Used primarily in analytical chemistry to detect and identify carbonyl compounds such as aldehydes and ketones. When reacted with these compounds, it forms brightly colored precipitates known as 2,4-dinitrophenylhydrazones, which can be analyzed for structure determination. It is also employed in the preparation of derivatives for spectroscopic analysis, aiding in the characterization of organic molecules. Additionally, it serves as a reagent in qualitative tests for carbonyl groups in organic synthesis and quality control processes.