Studies on complexation, accuracy, precision of CAS, PCV with CTAB in heavy metal ions, determination

Study of coordination compounds of heavy metal ions is of special interest since past due to their growing applications in science and technology. Complexation behavior of Triphenyl-Methane Dyes viz. Chrome Azurol-S,CAS; and Pyrocatechol Violet PCV, in the presence and absence of surfactant Cetyl Trimethyl Ammonium Bromide has been found to form stable water soluble pink colored complexes. CTAB have shown to increase sensitivity of the color reactions of these complexes with greater solubility and higher stability. The addition of some heavy metal ions such as Cu(II), Ni(II), Cd(II), Hg(II), and Pb(II), to these sensitized modified reagents resulted in the formation of intense, stable colored complexes. The composition of the complexes of metal ions under study remains same in both dyes CAS and PCV as 1:1, both in the absence and presence of CTAB except in case of Cd(II). In case of Cd(II) with CAS it is 1:1 and it changes as 1:2 in presence of CTAB. Dissociation constants pK values of dye- surfactant modified reagents has been calculated. Various analytical parameters including rate of color formation, effect of temperature and stability of color formation, range of adherence to Beers Law, Molar Extinction constants, Sensitivity, were studied for all systems in absence as well as in presence of CTAB.A simple, rapid, highly sensitized stable method has been proposed. Precision and Accuracy of the method suggested for microdetermination of metal ions was determined which shown suggested methods are both precise and accurate.