Used primarily as a qualitative reagent to detect phenolic compounds in organic and inorganic analysis. When added to a sample, it produces distinct color changes that help identify the presence of phenols—commonly giving purple, blue, or green hues depending on the specific phenol. Widely applied in pharmaceutical testing, quality control of raw materials, and educational laboratory experiments for functional group identification. Also utilized in wastewater analysis to detect aromatic pollutants and in the synthesis monitoring of phenolic resins. Its simplicity and rapid response make it a standard solution in analytical screening procedures.