Iodometric titration is a method for quantitative determination of the content of iodide ions in solutions using a reagent, where sodium diiodothiosulfate is used as such a reagent. This method is based on direct titration, either using dithiodomethane or using indicators, while the iodine concentration remains constant.
In general, iodine titration allows one to determine the concentration of molecular iodine in a substance.
Reagents. To carry out iodine titration, the following materials and reagents are required:
- Oxidizing reagent; - Metals to absorb iodine gas; - Iodometric indicator; — Titrant solutions.
Iodine titration scheme.
For titrimetric determination of substances containing iodine, redox reactions are used. For example, one can consider the reaction