A Spectrophotometric Study of the Saturated Mixed Complexes of Mercury(II)-Bromide-Iodide

1963 ◽  
Vol 2 (2) ◽  
pp. 340-345 ◽  
Author(s):  
Thomas G. Spiro ◽  
David N. Hume
Keyword(s):  
Spectrophotometric Study ◽  
Mixed Complexes

FERRIC SULPHATE COMPLEXES, AND TERNARY COMPLEXES WITH THIOCYANATE IONS

1955 ◽  
Vol 33 (10) ◽  
pp. 1591-1602 ◽  
Author(s):  
M. W. Lister ◽  
D. E. Rivington
Keyword(s):  
Ionic Strength ◽  
Constant Temperature ◽  
Equilibrium Constants ◽  
Spectrophotometric Study ◽  
Ternary Complexes ◽  
Ferric Sulphate ◽  
Extinction Coefficients ◽  
Mixed Complexes

A spectrophotometric study of solutions containing ferric and sulphate ions, and also ferric, sulphate, and thiocyanate ions, is reported. The measurements were made at constant temperature and ionic strength; the effect of varying acidity was also investigated. The data were interpreted with the help of the results of the first paper of this series. It is believed that the data show that FeSO4+ and FeHSO4++ ions are formed. Values are obtained for the equilibrium constants for their formation from simple ions, and for their extinction coefficients. At higher sulphate concentrations there is evidence for the appearance of Fe(SO4)2− and FeSO4•HSO4, and estimates are made of their equilibrium constants. When thiocyanate is also present, the data can best be interpreted by assuming that the complex FeSO4•SCN is formed, and at higher sulphate probably also Fe(SO4)2SCN−−. Values are obtained for the equilibrium constants for the formation of these species, and the results would indicate that mixed complexes of this type are formed as readily as 'simple' ones such as Fe(SO4)2−.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

The interaction of salicylaldehydebenzoylhydrazone with Ca2+ and Mg2+. A spectrophotometric study

1997 ◽  
Vol 94 ◽  
pp. 1195-1207 ◽  
Author(s):  
A Lyubchov ◽  
A Cossé-Barbi ◽  
JP Doucet ◽  
JM El Hage Chahine
Keyword(s):  
Spectrophotometric Study

Spectrophotometric Study of Iron, Nitrate and Phosphate in the River Gomti of Jaunpur City

2012 ◽  
Vol 1 (6) ◽  
pp. 7-9
Author(s):  
Shafqat Alauddin ◽  
◽  
Amresh Kumar ◽  
Shailendra Yadav ◽  
Tamheed Firdaus
Keyword(s):  
Spectrophotometric Study ◽  
Iron Nitrate

Organic compounds of fluorine. VII. Spectrophotometric study in the series of halofluoroethanes

1965 ◽  
Vol 30 (3) ◽  
pp. 745-751 ◽  
Author(s):  
B. Kakáč ◽  
M. Hudlický
Keyword(s):  
Organic Compounds ◽  
Spectrophotometric Study

Extraction of hafnium(IV) with organophosphorus reagents from solutions of mineral acids mixtures

1979 ◽  
Vol 44 (12) ◽  
pp. 3656-3664
Author(s):  
Oldřich Navrátil ◽  
Jiří Smola ◽  
Rostislav Kolouch
Keyword(s):  
Ionic Strength ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Synergic Effect ◽  
Salting Out ◽  
Initial Concentration ◽  
Mixed Complexes ◽  
Synergic Extraction ◽  
Mineral Acids

Extraction of hafnium(IV) was studied from solutions of mixtures of perchloric and nitric acids and of perchloric and hydrochloric acids for constant ionic strength, I = 2, 4, 6, or 8, and for cHf 4 . 10-4 mol l-1. The organic phase was constituted by solutions of some acidic or neutral organophosphorus reagents or of 2-thenoyltrifluoroacetone, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, or N-benzoyl-N-phenylhydroxylamine in benzene, chloroform, or n-octane. A pronounced synergic extraction of hafnium proceeds only on applying organophosphorus reagents from an aqueous phase whose acidity is not lower than 3M-(HClO4 + HNO3) or 5M-(HClO4 + HCl). The synergic effect was not affected markedly by a variation of the initial concentration of hafnium in the range 1 . 10-8 -4 .10-4 mol l-1, it lowered with increasing initial concentration of the organophosphorus reagent and decreasing concentration of the H+ ions. It is suggested that the hafnium passes into the organic phase in the form of mixed complexes, the salting-out effect of perchloric acid playing an appreciable part.

Spectrophotometric study of the complexation equilibria of cadmium ions with 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-diethylaminophenol (BrPADAP, ClPADAP)

1983 ◽  
Vol 48 (1) ◽  
pp. 52-59 ◽  
Author(s):  
Vlastimil Kubáň ◽  
Miroslav Macka
Keyword(s):  
Equilibrium Constants ◽  
Spectrophotometric Study ◽  
Graphical Analysis ◽  
Optimal Conditions ◽  
Cadmium Ions ◽  
Brij 35 ◽  
Ethanol Medium ◽  
Triton X ◽  
Derivatives Of

The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the reactions of formation of the ML and ML2 complexes of both reagents with cadmium(II) ions were determined by graphical analysis and numerical interpretation of the absorbance-pH curves by the modified SQUAD-G program. Optimal conditions were proposed for the spectrophotometric determination of Cd in 10% v/v ethanol medium in the presence of 0.1% w/v Triton X-100 or 1% w/v Brij 35. BrPADAP and ClPADAP are the most sensitive spectrophotometric reagents for the determination of cadmium(II) ions (ε = 1.28-1.44 . 105 mmol-1 cm2 at 560 nm and pH 8.0-9.5) with a high colour contrast in the reaction (Δλmax ~117 nm) and a selectivity similar to that of other N-heterocyclic azodyes (PAR, PAN, etc.).

Spectrophotometric study of the reactions of lanthanoids with bromopyrogallol red in the presence of cation active tensides

1982 ◽  
Vol 47 (2) ◽  
pp. 503-508 ◽  
Author(s):  
Irena Němcová ◽  
Pavla Plocková ◽  
Tran Hong Con
Keyword(s):  
Absorption Spectra ◽  
Photometric Determination ◽  
Spectrophotometric Study ◽  
Ternary Complexes ◽  
Optimal Conditions ◽  
Bromopyrogallol Red ◽  
Binary Complexes

The absorption spectra of the binary complexes of lanthanoids with bromopyrogallol red were measured and the formation of ternary complexes with cation active tenside, Septonex, was studied. Optimal conditions were found for the formation of these complexes and the possibility of their use in the photometric determination of lanthanoids was demonstrated on several examples.

Spectrophotometric study of the acid-base and optical properties of the 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-(diethylamino)phenol (BrPADAP, ClPADAP) and their complexation equilibria with zinc(II) ions

1982 ◽  
Vol 47 (10) ◽  
pp. 2676-2691 ◽  
Author(s):  
Miroslav Macka ◽  
Vlastimil Kubáň
Keyword(s):  
Equilibrium Constants ◽  
Spectrophotometric Study ◽  
Graphical Analysis ◽  
Alkaline Media ◽  
Acid Base ◽  
Ethanol Medium ◽  
Triton X ◽  
Mixed Water ◽  
Derivatives Of

The optical and acid-base characteristics of BrPADAP and ClPADAP were studied in mixed water-ethanol and water-DMF media and in 10% ethanol medium in the presence of cationic, anionic and nonionic tensides. The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the ML and ML2 complexes with zinc(II) ions were found by graphical analysis and numerical interpretation of the absorbance curves by the modified SQUAD-G program. Optimal conditions were found for the spectrophotometric determination of Zn(II) in the presence of 0.1% Triton X-100 or 1% Brij 35 in alkaline media with pH = 6.5-10. BrPADAP and ClPADAP are the most sensitive reagents (ε = 1.3-1.6 . 105 mmol-1 cm2 at 557 and 560 nm, respectively) for the determination of zinc with high colour contrast of the reaction (Δλ = 104 nm) and selectivity similar to that for the other N-heterocyclic azodyes (PAN, PAR, etc.).

Sign in / Sign up

Export Citation Format

Share Document