Kinetics and mechanism of oxidation oftris(ethylenediamine)-chromium(III) byN-bromosuccinimide

✍ Scribed by Ahmed A. Abdel-Khalek; Alaa E. D. M. Abdel-Hady; Mohamed F. El-Shahat

• Publisher: Springer
• Year: 1995
• Tongue: English
• Weight: 392 KB
• Volume: 20
• Category: Article
• ISSN: 0340-4285
• DOI: 10.1007/bf00141511

✦ Synopsis

In aqueous solutions, [Cr(en)3] 3+ aquates to [Cr(en)z-(H20)2] 3 § A kinetic study of the oxidation of [Cr(en)3] 3+ by N-bromosuccinimide (NBS)in aqueous solutions and water-alcohol solvent mixtures was performed. The reaction is first order with respect to both total [Cr m] and [NBS]. The rate is inversely dependent upon [H § in the 7.0-7.9 pH range, and varies with the co-solvent according to the order: MeOH > EtOH > PrOH. An appropriate mechanism, in which the deprotonated [Cr(en)2(OH)(H20)] 2+ is the reactive species, is suggested. Thermodynamic activation parameters have been calculated.