Chromotropic acid is widely used as a reagent in analytical chemistry for the detection and determination of various substances. It is particularly effective in colorimetric assays for formaldehyde, where it forms a purple-colored complex that can be measured spectrophotometrically. This application is crucial in environmental monitoring and industrial hygiene to assess formaldehyde levels in air, water, and products. Additionally, it serves as a chromogenic agent in the analysis of nitrites and nitrates, aiding in water quality testing. In biochemistry, chromotropic acid is employed in the quantification of reducing sugars and other carbohydrates, making it valuable in food science and metabolic studies. Its ability to form stable complexes with metal ions also makes it useful in metallurgical analysis and wastewater treatment processes.