Used primarily as a reagent to detect and characterize carbonyl compounds such as aldehydes and ketones. It reacts with these compounds to form brightly colored precipitates known as 2,4-dinitrophenylhydrazones, which are easy to observe and isolate. This reaction is widely used in qualitative organic analysis to confirm the presence of carbonyl groups. The derivatives formed have sharp melting points, making them useful for identification through melting point comparison. Also employed in spectrophotometric methods for the determination of carbonyl content in samples. Commonly used in teaching laboratories and research settings for functional group testing.