Product Short Description: Standard potassium iodide-iodate titrant standardized to 0.0125N . Titrate with potassium iodide-iodate titrant until end point and faint permanent blue color develops. Product Description: Standard potassium iodide-iodate titrant standardized to 0.0125N Titrate with potassium iodide-iodate titrant until end point and faint permanent blue color develops. Calculation of Results FORMULA: ppm sulfite as SO3 = ml of potassium iodide-iodate (RXSOL-62-5503-006) x 500 / ml SAMPLE Using a 50 ml sample, sulfite, in parts per million as SO3 is equal to the ml of RXSOL-62-5503-006 required multiplied by 10. Example: A 50-mL sample was titrated with 0.0125 N titrant and 6 mL of titrant was used at the endpoint. The concentration is 6 mL × 10 = 60 mg/L sulfite SO3 2– Sample volumes and multipliers Range (mg/L) Sample volume (mL) Titrant—potassium iodide-iodate Multiplier 0–100 50 0.0125 N 10 40–200 25 0.0125 N 20 100–500 10 0.0125 N 50 More than 500 05 0.0125 N 100