Differential pulse anodic stripping voltammetric study of zinc-ethylenediamine complex has been investigated using thin mercury film coated glassy carbon electrode at 30°C. The overall work was carried out at constant ionic strength (I = 0.20 mol dm -3 ) and pH (9.10±0.10). The electrode processes were found to be reversible and diffusion controlled. The results revealed that zinc forms three (...

the acidity constants of some amino acids (am) were determined by potentiometric ph titration. the stability constants of the 1:1 complexes formed between m2+: ca2+, mg2+, mn2+, co2+, ni2+, cu2+ or zn2+ and am2-, were determined by potentiometric ph titration in aqueous solution (i = 0.1 m, nano3, 25°c). the order of the stability constants was reported. it is shown that the stability of the bi...

The complexation reactions between Tl+ and Pb2+ ions and crown ethers 12-crown-4(12C4), 15-crown-5 (15C5), benzo-15-crown-5 (B15C5), 18-crown-6 (18C6), dicyclohexyl-18-crown-6 (DC18C6) and aza-18-crown-6 (A18C6) were studied in 90% acetonitrile and 90% ethanol solutions at 25 °C, using an a.c. polarographic technique. The stoichiometry and stability of the complexes we...

The stability constants and complexation reaction between L-glutamine, L-arginine andglycine with Zn (II) , Co (II) and Ni (II) were studied potentiometrically in aqueous solution at25° C and μ=0.1 M KNO3. The overall stability constants log β´s of all species are obtained bycomputer refinement of pH-volume data using BEST computer program. Several models weretested and the lowest δFIT, the bes...

in this work, a new spectrophotometric method for the determination of trace amount of cobalt (іі) ionwas investigated and the stability constant of the related complex was evaluated 2.174 × 104. in the cobalt(іі)-piroxicam complex, the maximum absorbance wavelength is 570 nm and the linearity of calibrationcurve was investigated (5-10 ppm). the relative standard deviation for seven replicate e...

The acidity constants of some amino acids (Am) were determined by potentiometric pH titration. The stability constants of the 1:1 complexes formed between M2+: Ca2+, Mg2+, Mn2+, Co2+, Ni2+, Cu2+ or Zn2+ and Am2-, were determined by potentiometric pH titration in aqueous solution (I = 0.1 M, NaNO3, 25°C). The order of the stability constants was reported. It is shown that the stability of the bi...

stability of the π-π stacking interactions in the ben||substituted-coronene and hfben||substituted-coronene complexes was studied using the computational quantum chemistry methods (where ben and hfben are benzene and hexaflourobenzene, || denotes π-π stacking interaction, substituted-coronene is coronene molecule which substituted with four x groups, and x= nh2, ch3, oh, h, f, cf3, cn and no). ...

Herein, a theoretical study on the stability of some vic-dioxime complexes of Ni(II), Pd(II) and Pt(II) in gas and aqueous phases is reported. The DFT/M06/SDD and DFT/M06/6-31G+(d,p) levels of theory were adopted for the metal ions and for every other element respectively. Structural analyses of investigated complexes have revealed square planar geometries stabilized by two O–H⋯Cl hydrogen bond...