Transition Metal Chemistry

, Volume 16, Issue 2, pp 145–148 | Cite as

Electron transfer at tetrahedral cobalt(II). Part 1. Kinetics of bromate ion reduction

  • Godwin Adefikayo Ayoko
  • Johnson Femi Iyun
  • Ibrahim Faskari El-Idris
Full Papers


The bromate ion reduction by 12-tungstocobaltate(II) anion has been investigated. The reaction obeys the empirical rate law:-d[reductant]/dt=5(a+b[H+]2)[BrO 3 ][reductant]: where a=(2.49±0.18)×10−4M−1 s−1, b=(4.65±0.20)×10−5M−3s−1 at 24.5±0.1°C [H+]=0.05–1.50M and I=2.0M (NaClO4). This rate law is interpreted in terms of parallel reactions of BrO 3 and H2BrO 3 + . On the basis of the observed anion catalysis, substitution intertness of the reductant and Marcus type linear free energy relations, the outer sphere mechanism is proposed for both pathways.


Free Energy Cobalt Inorganic Chemistry Catalysis Electron Transfer 
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Copyright information

© Chapman and Hall Ltd 1991

Authors and Affiliations

  • Godwin Adefikayo Ayoko
    • 1
  • Johnson Femi Iyun
    • 1
  • Ibrahim Faskari El-Idris
    • 1
  1. 1.Department of ChemistryAhmadu Bello UniversityZariaNigeria

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