Used primarily as a reagent in analytical chemistry for the detection and determination of various compounds, particularly phenols and aromatic amines. It reacts with these compounds to form colored products, making it valuable in spectrophotometric analysis. Additionally, it serves as an intermediate in the synthesis of dyes and pigments, contributing to the production of vibrant colors in industrial applications. Its role in organic synthesis extends to the preparation of pharmaceuticals and other fine chemicals, where it acts as a building block for more complex molecules.