Collect. Czech. Chem. Commun.
1980, 45, 21-25
https://doi.org/10.1135/cccc19800021
Kinetics and mechanism of oxidation of Cr(II) ions by tetrachloromethane
Peter Ševčík and Miroslav Khír
Department of Physical Chemistry, Comenius University, 816 31 Bratislava
Abstract
Kinetics of the redox reaction of Cr(II) ions with tetrachloromethane has been studied in H2O-CH3OH-HClO4 and H2O-CH3COOH-HClO4. In the redox reaction 2 moles of Cr(II) are consumed per one mol of CCl4, and CrCl2+ and CrCCL2+3 ions are formed in the same amounts. Second order rate constants (k293 = 2.31 mol-1 s -1 in 50% CH3OH, k293 = 1.66 l . mol-1 s-1 in 50% CH3COOH) are independent of H+ ions concentration.The rate determining step is an inner sphere transfer of the halogen from CCl4 to Cr(II), the Cr-Cl-C bridge structure being retained in both media.