Used primarily as an intermediate in the synthesis of dyes and pigments, particularly in the production of azo dyes, which are widely applied in the textile industry. It also serves as a reagent in organic synthesis for the preparation of various chemical compounds. In analytical chemistry, it is employed as a colorimetric agent to detect and quantify specific substances. Additionally, it finds use in research laboratories for studying oxidation-reduction reactions and as a model compound in photochemical studies.