ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Redox reactions of complexes of cations in higher oxidation states. VII. Kinetics of the redox reaction of the manganese(III) ions with hydrazoic acid

Ľ. Treindl and M. Mrákavová

Department of Physical Chemistry, Faculty of Natural Sciences, Komenský University, 81631 Bratislava

Abstract: The kinetics and mechanism of the redox reaction of the Mn(III) ions with hydrazoic acid in the medium of 54% acetic acid was studied. The curve representing the dependence of the rate constant on the concentration of azides rises linearly at first, reaches a maximum and afterwards sinks non-linearly. The values of the enthalpy and entropy of activation depend on temperature considerably. From the temperature dependence of these values the activation heat capacity was calculated ∆C_p^≉= 1569 J mol^-1 К^-1. The probable reaction mechanism according to which the redox reaction goes through the inter­ mediary complex MnHN₃(Ac)₂⁺ is discussed. However, in the region of higher concentrations of azides the less reactive Mn(HN₃)₂(Ac)₂⁺ complex ion com­ petes with that intermediary complex.

Full paper in Portable Document Format: 312a145.pdf

Chemical Papers 31 (2) 145–152 (1977)