Kinetics and Mechanism of Oxidation of Some Aldopentoses by Quinquevalent Vanadium in Sulphuric Acid

School of Studies in Chemistry, Jiwaji University, Gwalior (M.P.) Department of Chemistry, Govt. Science College, Gwalior Manuscript received 11 January 1977, accepted 16 January 1978 The oxidation of D-xylose, L-arabinose and D-ribose by quinquevalent vanadium in sulphuric acid medium has been found to be of first order with respect to both oxidant and substrate concentrations. The rate of oxidation has been found to increase with first power of [H+] in 2.0M to 4.5M acid concentration range and with second power of [H+] in higher acid range>4.5M at constant HSO\(_4^-\), concentration. The increase in oxidation rate with HSO\(_4^-\); concentration at constant n+ concentration has been also observed. The thermodynamic parameters have been evaluated from Arrhenius plots. The effect of changing the composition of acetic acid -water binary mixture on rate has indicated the reaction to be ion-dipole type. Possible reaction steps have been also proposed