Mishra , A. P and Khan , Raju and Pandey, Ravi Ranjan (2010) Biological aspects kinetic analysis of the vanadium (V) to vanadium (IV) by (EDTA) in sulphuric acid medium. NATIONAL ACADEMY SCIENCE LETTERS-INDIA, 33 (5-6). pp. 149-152. ISSN 0250-541X

Preview

PDF - Submitted Version Download (2208Kb) | Preview

Abstract

Catalytic oxidative behavior of ethylenediamminetetraacetic acid (EDTA) in the context of reduction of vanadium(V) to vanadium(IV). has been investigated. The reaction was followed spectrophotometrically in the acidic medium by measuring the decrease in absorbance of the pale yellow complex [VOSO(4 center dot)H(2)O](+) at 365 nm. Spectrophotometrically evidence has been obtained for a complex formation between the respective reactive species of vanadium(V) and EDTA prior to electron transfer. The reaction is first-order with respect to each [EDTA] and [vanadium(V)] catalysed by H(2)SO(4). The reaction does not involve one-step two-electron transfer as vanadium(III) could not he detected under the experimental conditions. The activation parameters Ea = 65 kJ mol(-1). Delta H# = 63 kJ mol(-1) Delta S# = -212 J K(-1) mol(-1). and Delta G# = 131 kJ mol(-1) are calculated and discussed. Reaction products are also examined; the formation of vanadium(IV) aqua ion was observed confirming the single-electron sequence.

Item Type:	Article
Subjects:	Chemistry Physics
Divisions:	UNSPECIFIED
Depositing User:	Ms Neetu Chandra
Date Deposited:	23 Feb 2012 06:36
Last Modified:	23 Feb 2012 06:38
URI:	http://npl.csircentral.net/id/eprint/31

Actions (login required)

View Item