Kinetics of Ion-Pair Effect of Aquation of Bromopentaammine Cobalt(III) Complex in Different Dicarboxylate Media

Abstract:

The rate of aquation of bromopentaammine cobalt(III) ion in the presence of different types of dicarboxylate solutions containing tert-butanol (40% V/V) have been measured spectrophotometrically at different temperatures (30-600°C) in the light of the effects of ion-pairing on reaction rates and mechanism. The thermodynamic and extrathermodynamic parameters of activation have been calculated and discussed in terms of solvent effect on the ion-pair aquation reaction. The free energy of activation ∆Gip* is more or less linearly varied among the studied dicarboxylate ion-pairing ligands indicating the presence of compensation effect between ∆Hip* and ∆Sip*. Comparing the kip values with respect of different buffers at 40% of ter-butanol is introduced.

• Periodical: Advanced Materials Research (Volume 324)
• Pages: 166-169
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.324.166
• Online since: August 2011
• Authors: Farah Zeitouni, Gehan El-Subruiti, Ghassan Younes, Mohammad Amira
• Keywords: Cobalt(III) Complexes, Dicarboxylate Media, Ion-Pairing, Kinetics of Aquation

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