Used in analytical chemistry for calibration of instruments such as ion-selective electrodes and spectrophotometers to accurately measure iodide concentrations in samples. Commonly applied in environmental testing to determine iodide levels in water and soil. Essential in clinical laboratories for quantifying iodide in biological fluids like urine and blood, supporting thyroid function assessment. Also used in quality control processes in pharmaceutical manufacturing where iodide content must be precisely monitored. Suitable for titration methods and standardization of other reagents in redox reactions.