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6826288 
Journal Article 
Oxidation of ninhydrin by quinolinium dichromate (QDC) - A kinetic and mechanistic approach 
Chimatadar, SA; Salunke, MS; Nandibewoor, ST 
2006 
Yes 
Journal of the Indian Chemical Society
ISSN: 0019-4522 
83 
11 
1093-1096 
WOS:000243095200005 
Quinolinium dichromate (QDC) oxidation of ninhydrin has been studied spectrophotometrically, in an aqueous perchloric acid medium at constant ionic strength of 0.025 mol dm(-3) and at 25 degrees C. The reaction is first order in quinolinium dichromate concentration and less than unit order each in ninhydrin and H+ ion concentrations. Increase in perchloric acid concentration accelerates the reaction rate. The main reaction products are chromium(III) and phthalic acid. Phthalic acid was identified by spot test, IR and NMR spectra. The added product chromium(m) retards the reaction rate whereas added phthalic acid did not show any significant effect on. the rate of, reaction. The ionic strength and dielectric constant did not have any appreciable effect on the reaction rate. On the basis of experimental results a suitable mechanism is proposed. The activation parameters were evaluated and discussed. 
ninhydrin; quinolinium dichromate