Potentiometric Studies of Complex Equlibria of Ca\(^{II}\), Mg\(^{II}\) and Zn\(^{II}\) with 5-Sulphosalicylic Acid in Cationic Micelles of CTAB: Experimental Investigation

Abstract

In various compositions of cetyltrimethylammonium bromide (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5% w/v), metal ligand complex species of 5-sulphosalicylic acid with Ca^II, Mg^II, and Zn^II metal ions have been examined potentiometrically (CTAB). The experiment was conducted at 303 K while using NaCl to maintain an ionic strength of 0.16 mol dm^-3. The dynamic species belongs to 5-sulphosalicylic acid are LH₂^- and LH^2-. Based on statistical characteristics such as skewness, \(\chi^{2}\), Kurtosis, and crystallographic R-factor, the best fit of complicated speciation has been chosen. The complexation of 5-sulphosalicylic acid with metal ions resulted in the formation of ML₂H, ML₂H₂, and ML₃H₃ type complexes. On the basis of electrostatic grounds, the change in stability of complex species with surfactant composition has been depicted. The distribution of chemical species with regard to pH and various compositions of medium, as well as possible complicated equilibria, is also investigated.