Used primarily in analytical chemistry as a selective reagent for the detection and precipitation of potassium ions. It forms a distinctive yellow crystalline precipitate when reacting with potassium in solution, making it valuable in qualitative inorganic analysis. This property is exploited in laboratory settings to separate potassium from other alkali metals like sodium. Also utilized in some specialized sensor applications for monitoring potassium levels in environmental or industrial samples. Its high selectivity for potassium makes it useful in educational labs for demonstrating ion identification techniques.