Sulfide Calculator
Definition: In the iodometric method, a measured excess of iodine reacts with sulfide in acidic solution. The remaining iodine is back-titrated with sodium thiosulfate.
Sulfide (mg/L as S²⁻) =
[(A × B) − (C × D)] × 16,000 / V
A = iodine volume (mL)
B = iodine normality
C = sodium thiosulfate volume (mL)
D = sodium thiosulfate normality
V = sample volume (mL)
Method basis: Standard Methods for the Examination of Water and Wastewater, Method 4500-S²⁻ F — Iodometric Method.