Sodium Nitrite Test: Rinse and fill 25 mL sample tube (#9198R) to 25 mL mark with water to be tested. Add 25 drops R-0729 Sulfuric Acid 50%. Swirl to mix.
CAUTION: R-0729 Sulfuric Acid 50% is a corrosive acid. Handle carefully. Using 1.0 mL pipet (#9010), add R-0730 Permanganate Reagent dropwise, swirling and counting after each drop, until sample changes from colorless to a faint but permanent pink (Fig. 1), which persists for at least 1 minute. Multiply drops of R-0730 Permanganate Reagent by 100. Record as parts per million (ppm) sodium nitrite (NaNO2).
NOTE: For results as nitrite (NO2– ), multiply sodium nitrite (NaNO2) concentration by 0.67.
