Used as a sensitive reagent for the detection and quantitative determination of nickel in analytical chemistry. It forms a bright red precipitate with nickel ions, making it valuable in qualitative analysis and spectrophotometric methods. Also employed in environmental testing to monitor nickel contamination in water and soil samples. Applied in metallurgy and industrial processes for nickel plating control and purification. Its high selectivity for nickel over many other metal ions enhances accuracy in analytical procedures.