SPECTROPHOTOMETRIC STUDY OF THE REACTION BETWEEN IRON (III) AND KOJIC ACID
- 1 March 1961
- journal article
- Published by Canadian Science Publishing in Canadian Journal of Chemistry
- Vol. 39 (3) , 510-525
- https://doi.org/10.1139/v61-062
Abstract
A method introduced by Vareille enables calculation of formation constants of colored metallic complexes in solution by making appropriate deductions from the presence of isobestic points in the spectra of suitably chosen solutions. The rationale of this method is derived rigorously, and its application extended to include cases where three complexes are present together in certain regions of pH. These principles are applied to derive for the ferric kojates the following formation constants, at 25 °C and ionic strength 0.5: log K1 = 10.16, log K2 = 8.29, log K3 = 6.90. The relationship between pH and pL for the experimental conditions is calculated, thereby enabling the estimation of the distribution of the metal among the several species in each solution and the absorption spectrum of each complex.Keywords
This publication has 3 references indexed in Scilit:
- On the Method of Continuous Variations.Acta Chemica Scandinavica, 1955
- Quantitative studies of the avidity of naturally occurring substances for trace metals. 3. Pteridines, riboflavin and purinesBiochemical Journal, 1953
- Colorimetric Determination of Iron with Kojic AcidIndustrial & Engineering Chemistry Analytical Edition, 1941