Chemical Speciation in the Copper (I)-Ammonia-Chloride System

1995 ◽  
Vol 48 (7) ◽  
pp. 1283 ◽  
Author(s):  
JS Solis ◽  
G Hefter ◽  
PM May
Keyword(s):  
Ionic Strength ◽  
General Equilibrium ◽  
Chemical Speciation ◽  
Ionization Constant ◽  
Protonation Constant ◽  
Formation Constants ◽  
Glass Electrode ◽  
Ternary Complexes ◽  
Chloride System ◽  
Binary And Ternary Complexes

Chemical speciation in the system CuI/NH3/Cl- which may be represented by the general equilibrium pCuI(aq)+qNH3(aq)+rCl-(aq)↔ Cup(NH3)qClr(p-r)+(aq) has been studied by glass electrode potentiometry at 25.0°C and an ionic strength of 1.00 M (NaClO4). A number of binary and ternary complexes were detected with formation constants, βpqr: logβ120 = 11.381�0.077, logβ111 = 8.920�0.045, logβ112 = 8.82�0.18 and logβ121 = 11.33�0.24. The ionization constant of water (pKw) and the protonation constant of ammonia (pKa) obtained by the same procedures were 13.7462�0.0012 and 9.4613�0.0010 at I = 1 (NaClO4), and 13.7165�0.0010 and 9.4521�0.0007 at I = 1 (NaCl) respectively.

Equilibrium Studies of Binary and Ternary Complexes of Palladium(II) Involving Amino Acids

1993 ◽  
Vol 58 (5) ◽  
pp. 1103-1108 ◽  
Author(s):  
Mohamed M. Shoukry ◽  
Eman M. Shoukry
Keyword(s):  
Amino Acids ◽  
Relative Stability ◽  
Ternary Complex ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Conductivity Measurements ◽  
Equilibrium Studies ◽  
Binary And Ternary Complexes ◽  
Binary Complexes

The formation constants of the binary and ternary complexes of palladium(II) with diethylenetriamine and amino acids as ligands have been determined potentiometrically at 25 °C in 0.1 M NaNO3 solution. The relative stability of each ternary complex was compared with that of the corresponding binary complexes in terms of ∆logK values. The mode of chelation was ascertained by conductivity measurements.

scholarly journals Stability Studies of Transition Metal Chelates of 5-Bromosalicylidene-4-methoxyaniline andSalicylidene-2,3-dimethylaniline as Ligands

2011 ◽  
Vol 8 (4) ◽  
pp. 1911-1915
Author(s):  
N. G. Nadkarni ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Transition Metal ◽  
Stability Constants ◽  
Metal Chelates ◽  
Ternary Complexes ◽  
Water Medium ◽  
Stability Studies ◽  
Binary And Ternary Complexes ◽  
Transition Metal Chelates ◽  
The Stability

Binary and ternary complexes of the type M-Y and M-X-Y [M = Mn(II), Ni(II), Cu(II) and Zn(II); X = 5-bromosalicylidene-4-methoxyaniline and Y = salicylidene-2,3-dimethylaniline] have been examined pH-metrically at 27±0.5°C and at constant ionic strength, μ = 0.1 M (KCl) in 75 : 25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated.

A stability and equilibrium study on Cd – salicylidene tris(hydroxymethyl) methylamine – chloride binary and ternary complexes

1992 ◽  
Vol 70 (3) ◽  
pp. 877-879
Author(s):  
Refat Abdel-Hamid ◽  
Mohamed T. El-Haty
Keyword(s):  
Binary System ◽  
Aqueous Medium ◽  
Chloride Ion ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
Equilibrium Study

Binary and ternary complexes of Cd(II) with salicylidene tris(hydroxymethyl) methylamine and chloride ion at 298 K were studied polarographically at I = 0.1 mol dm−3 NaClO4 in 30% (v/v) DMF – aqueous medium at pH 10.2. The overall formation constants were found to be, for the binary system, log β1 = 3.55 ± 0.03 and log β2 = 5.40 ± 0.07 and, for the ternary one, log β11 = 7.64 ± 0.06 and log β12 = 9.56 ± 0.06. Keywords: formation constants, binary and ternary complexes of Cd(II).

Ionization of Water in Concentrated Potassium Halide Media

2000 ◽  
Vol 53 (5) ◽  
pp. 369 ◽  
Author(s):  
Faradj K. Samani ◽  
Stephen G. Capewell ◽  
Pal M. Sipos ◽  
Peter M. May ◽  
Glenn Hefter
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
High Precision ◽  
Excellent Agreement ◽  
Ion Pairs ◽  
Formation Constants ◽  
Glass Electrode ◽  
Ionic Product ◽  
Ionization Of Water ◽  
Potassium Halide

The ionic product of water, pKw = –log[H+][OH–], has been determined as a function of ionic strength (I ) in concentrated aqueous solutions of KCl, KBr and KI at 25˚C by high-precision glass electrode potentiometric titrations. The pKw values obtained are in excellent agreement with, but generally more precise than, literature data. At I > 1 M the pKw values increase smoothly and show systematic differences in the order KCl < KBr < KI, consistent with the decreasing H+-acceptor ability of the medium anions. Analogous behaviour is observed in MCl solutions, with pKw values varying in the order NaCl < KCl < CsCl. Formation constants of MOH0 ion pairs derived from these data are consistent with literature values.

Interligand interaction in ternary complexes of Zn(II) and Cd(II) with dipeptides and aminoacids

1994 ◽  
Vol 72 (4) ◽  
pp. 1107-1110 ◽  
Author(s):  
Alexander Varghese Vaidyan ◽  
Pabitra K. Bhattacharya
Keyword(s):  
Ionic Strength ◽  
Aqueous Medium ◽  
Computer System ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
The Stability ◽  
Interligand Interaction

The stability constants of binary and ternary complexes [MA], [Ma2], and [MAL] (where M = Zn(II) or Cd(II); A = glycylglycine, glycyl L-alanine, glycyl L-leucine; L = α-alanine phenylalanine, tyrosine, tryptophan, or L-histidine) in aqueous medium have been determined potentometrically at 25 °C and an ionic strength of 0.2 M NaClO4 (0.2 mol dm−3) using a computer system. It is observed that Δ log K of MAL complexes has low negative or positive values. Probable reasons have been discussed.

scholarly journals Potentiometric and UV Spectral Studies of Binary and Ternary Complexes of Some Metal Ions withN-Acetylcysteine and Amino Acids

2009 ◽  
Vol 6 (s1) ◽  
pp. S117-S122 ◽  
Author(s):  
Shaesta Quyoom ◽  
Badr-Ud-Din Khan
Keyword(s):  
Amino Acids ◽  
Metal Ions ◽  
Aqueous Medium ◽  
Dissociation Constants ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Acid Dissociation ◽  
Spectral Studies ◽  
Binary And Ternary Complexes ◽  
Structural Nature

The formation constants of the binary 1:1 and 1:2 complexes of Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) withN-acetylcysteine (NAC) and 1:1:1 ternary complexes of the said metal ions with NAC as a primary ligand and some biologically important amino acids as secondary ligands have been determined potentiometrically in aqueous medium. Acid dissociation constants of the ligands used and the formation constants of the binary and the ternary complexes were determined at 25 °C and in ionic strength I=0.1 mol dm-3(KNO3).The formation constants of the 1:1 complexes were found to be higher than 1:2 complexes and the metal ions follow the order Hg(II) >Cu(II) >Cd(II) >Zn(II). In addition UV-spectral studies of the NAC-Metal (II) complexes have also been conducted at appropriate pH values to give further information about the structural nature of NAC- Metal (II) complexes in aqueous medium.

scholarly journals Potentiometric and Blood Plasma Simulation Studies of Nickel(II) Complexes of Poly(amino)amido Pentadentate Ligands: Computer Aided Metal-Based Drug Design

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Sebusi Odisitse ◽  
Graham E. Jackson
Keyword(s):  
Ionic Strength ◽  
Blood Plasma ◽  
Formation Constants ◽  
Glass Electrode ◽  
Plasma Simulation ◽  
Simulation Studies ◽  
Plasma Model ◽  
Computer Aided ◽  
Pentadentate Ligands

The thermodynamic equilibria of nickel(II) with N,N′-di(aminoethylene)-2,6-pyridinedicarbonylamine (L1), Bis-(N,N-dimethylethyl)-2,6-pyridinedicarboxamide (L2), and N,N′-bis[2(2-pyridyl)-methyl]pyridine-2,6-dicarboxamide (L3) have been studied at 25°C and an ionic strength of 0.15 mol dm−3by glass electrode potentiometry. The protonation and formation constants added to blood plasma model predict that Cu(II) competes effectively against Ni(II), Zn(II), and Ca(II) for these ligandsin vivo.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) ions with N-(2-hydroxybenzylidene)-2,3-dimethylaniline as Primary Ligand and N-(2-hydroxy-1-naphthylidene)-4-nitroaniline as Secondary Ligand

2011 ◽  
Vol 8 (2) ◽  
pp. 859-862 ◽  
Author(s):  
A. K. Mapari ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Transition Metal ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
The Stability ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M=Co(II), Ni(II), Cu(II) and Zn(II); X=N-(2-hydroxybenzylidene)-2,3-dimethylaniline and Y =N-(2-hydroxy-1-naphthylidene)-4-nitroaniline] have been examined pH-metrically at 27±0.5 °C and at constant ionic strength, μ=0.1 M (KCl) in 75:25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated.

scholarly journals Thermodynamics of binary and ternary complexes of 3-amino-1, 2, 4-triazole and aminoacids with Ni(II) and Co(II) metal ions

2005 ◽  
Vol 70 (8-9) ◽  
pp. 1057-1066 ◽  
Author(s):  
Ayse Erçag ◽  
Tuba Sismanoglu ◽  
Suheyla Pura
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Glutamic Acid ◽  
Driving Force ◽  
Ternary Complex ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
Enthalpy Changes ◽  
Binary Complexes ◽  
The Stability

The stability constants of the 1:1 binary complexes of Ni(II) and Co(II) with 3-amino-1,2,4-triazole (AT), leucine (Leu) and glutamic acid (Glu), and the 1:1:1 ternary complex of them and the protonation constants of the ligands were determined potentiometrically at a constant ionic strength of I = 0.10 mol L-1 (NaClO4) in aqueous solutions at 15.0 and 25.0 ?C. The thermodynamic parameters ?Gf0, ?Hf0 and ?Sf0 are reported for the formation reactions of the complexes. The enthalpy changes of all the complexations were found to be negative but the entropy changes positive. While the driving force for the formation of the Ni(II), Co(II) ? AT complexes is the enthalpy decrease, the driving force for the ternary complexes of AT is the entropy increase.

scholarly journals Characterization by Potentiometric Procedures of the Stability Constants of the Binary and Ternary Complexes of Cu(II) and Duloxetine Drug with Amino Acids

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Amal M. Al-Mohaimeed ◽  
Asma A. Alothman
Keyword(s):  
Amino Acids ◽  
Stability Constants ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Planar Geometry ◽  
Binary And Ternary Complexes ◽  
Mass Spectral ◽  
Binary Complexes ◽  
Potentiometric Titration Method ◽  
The Stability

Potentiometric titration method has been used to define stoichiometries and stability constants of ternary complexes of Cu(II) with duloxetine (D) and some selected amino acids (L). The protonation constants of the ligands and the stability constants of the binary and ternary complexes of Cu(II) with the ligands were calculated from the potentiometric data using the HYPERQUAD program. The formation constants of the complexes formed in aqueous solutions and their concentration distributions as a function of pH were evaluated at 25°C and ionic strength 0.10 mol·L−1 NaNO3. Respective stabilities of ternary complexes have been determined compared with the corresponding binary complexes in terms of Δlog  K and %R.S. values. A novel binary and ternary duloxetine (D) drug with glycine and its Cu(II) complexes has been synthesized and characterized by several spectroscopic methods. Electronic spectra and magnetic susceptibility measurements reveal square planar geometry for both complexes. The elemental analyses and mass spectral data have justified the [Cu(D)(Gly)] and [Cu(D)Cl(H2O)] composition of complexes, where D = duloxetine and Gly = glycine. The EPR spectra of Cu(II) complexes support the mononuclear structures. Thermal properties and decomposition kinetics of Cu(II) complexes are investigated.

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