Tiron (Chemical Name: Disodium 4,5-Dihydroxy-1,3-benzene Disulfonate; CAS No. 149-45-1; Formula: C₆H₄Na₂O₈S₂) is a water-soluble white to off-white powder known for its strong metal-chelating properties. It is widely used as a reagent for titanium, iron, and other metal ion analysis in analytical chemistry and spectrophotometry.