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

Kinetics of Hydroxylamine Reduction by Bivalent Chromium

P. Ševčík and Ľ. Treindl

Department of Physical Chemistry, Faculty of Natural Sciences, Komenský University, Bratislava 1

Abstract: The results of kinetic study of hydroxylamine reduction by bivalent chromium are described. The reaction is one of the first order with respect to the bivalent chromium concentration as well as to hydroxylamine concentration. The rate constant does not depend on the concentration of hydrogen ions. In the presence of chloride ions the reaction rate increases what may be explained by the formation of Cr(II) complexes with chloride ions which react with hydroxylamine faster than Cr(II) hexa-aquo complexes. By using the Eyring equation the kinetic thermodynamic quantities have been determined: ΔH^# = 11.0 kcal mole^-1 and  ΔS^#= —30.1 cal deg^-1 mole^-1 at ionic strength 1.3. On the basis of kinetic data obtained by Polarographie method the probable reaction mechanism is discussed.

Full paper in Portable Document Format: 2311-12a822.pdf

Chemical Papers 23 (11-12) 822–828 (1969)