Spectrophotometric determination of hydrogen peroxide using tris(1,10-phenanthroline)iron(II)

Abstract

Hydrogen peroxide reacts with iron(II) in acidic medium, and the unreacted iron(II) forms a stable complex with 1,10-phenanthroline that absorbs at 508 nm. This indirect spectrophotometric method, based on the absorbance reduction of tris(1,10-phenanthroline)iron(II) was utilised for the determination of hydrogen peroxide. The effective molar absorptivity for H₂O₂ is 2.22 × 10⁴ l mol^–1 cm^–1. The proposed procedure is sensitive and has been applied to the analysis of commercial peroxide samples. Possible interferences are discussed.