The Kinetics if the Hydrolysis of Trans-K[Cr(ox)2(H2O)2].3H2O

Mohamad Ali Abdullah, & Bakhtyar Kamal Aziz

College of Science, University of Sulaimani

In the present work, the kinetics of the hydrolysis of the complex Trans-K[Cr(ox)2(H2o)z]'3Hzo have
been srudied in aqueous media at (pH:4.i,5.1;5.6 and 6.3) _(trr:0-4 NaNO3)' The hydrolysis rate was
found to be acid dependent and show a linear increase witn [U*1-'. The activation parameters for the
reactions are (Ear45.77 kJ;;l',;ft*, =+:.tS kJ mol-r and ASlr = -Zna J mo1-1) and (Eaz=81'21 kJ mol'
ilHi;=tg.59 r.j *or t and ASf2 : J mol-t). The observed rate constants are in good agreement
with that reported by Kallen and Hamm for the anation of {Cis-[Cr(ox)z6zOh]-]'

Keywords: Cr (lII) complex, kinetic lability, hydrolysis'


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