The oxalic acid catalysed oxidation ofbis(2,4,6-tripyridyl-1,3,5-triazine)-iron(II) by chromium(VI) in acetate buffer

✍ Scribed by Tatakuntla Satyanarayana; Nageswara Rao Anipindi; Veeraputhiran Subbiah; Madhusudan Waman Pandit

• Publisher: Springer
• Year: 1993
• Tongue: English
• Weight: 284 KB
• Volume: 18
• Category: Article
• ISSN: 0340-4285
• DOI: 10.1007/bf00136060

✦ Synopsis

The reaction between bis (2,4,6-tripyridyl-l,3,5-triazine)iron(II), Fe(TPTZ)~ + and chromium(VI) in acetate buffers is very slow. However, in the presence of oxalic acid (catalyst) it is very fast and is completed within 10 s. The reaction was studied in the 3.6-5.6 pH range using stoppedflow spectrophotometry. The reaction is first order in the substrate and zero order in the oxidant. The rate of the reaction increases with the increase in pH. Kinetic evidence for complexation between the substrate and the catalyst was obtained and a mechanism involving the formation of an ion-pair between Fe(TPTZ)~ + and the oxalate ion is proposed.