Kinetic studies on the reaction between [Co(NH3)5N3]Cl2 and ascorbic acid: Effect of surfactant, polymer and their mixture

Gelatin has multitalented applications. In its applications it is normally used with surfactants. The ionic surfactants readily form complexes with ionic gelatin molecules through Coulomb interaction. The effect of gelatin-CTAB interaction on the dynamics of the oxidation of ascorbic acid by [Co(NH3)5N3]Cl2 at constant pH and ionic strength has been studied spectrophotometrically. The CTAB, gelatin and their mixture have effects on the rate. The rate decreases with CTAB up to its CMC then passes through a maximum. The rate also decreases with gelatin and passes through a minimum at ∼ 0.10% (w/v). In the presence of gelatin CTAB has no significant effect on the rate below its CMC then the rate increases for each different gelatin concentrations. At a lower concentration region of gelatin rate enhancement is small whereas maximum at 0.04% (w/v). CMC of CTAB in the presence of gelatin at different temperatures has been determined which corroborates with the general features of temperature effect on it.