Kinetics and mechanism of the hypochlorous acid-trithionate reaction

György Cseko, Evelin Rauscher, Attila K. Horváth

Research output: Contribution to journalArticle

3 Citations (Scopus)


The trithionate-hypochlorous acid reaction has been studied by the stopped-flow technique and conventional spectrophotometry between pH = 6.59-12.2 monitoring absorbance-time profiles at 285 and 225 nm. We showed that the formal kinetic order of Cl(I) is nearly 2; however, those of hydrogen ion and trithionate are significantly lower than unity, suggesting complex kinetics. It was also demonstrated that both forms of Cl(I) are kinetically active within the concentration range studied. Simultaneous evaluation of the kinetic curves revealed that the reaction was initiated by a formal Cl+ transfer to the partially negatively charged β-sulfur of trithionate. S 3O6Cl- formed in the first step was also found to be equilibrating with S3O6OH- via a simple chlorine-OH exchange reaction followed by their subsequent oxidation of hypochlorite and hypochlorous acid, respectively. A six-step kinetic model is proposed and discussed with having four fitted and four fixed parameters.

Original languageEnglish
Pages (from-to)8836-8842
Number of pages7
JournalJournal of Physical Chemistry A
Issue number36
Publication statusPublished - Sep 12 2013


ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this