The effect of pressure on complex ion equilibria

1956 ◽  
Vol 9 (1) ◽  
pp. 54 ◽  
Author(s):  
AH Ewald ◽  
SD Hamann
Keyword(s):  
Free Energy ◽  
Dissociation Constant ◽  
Atmospheric Pressure ◽  
Qualitative Agreement ◽  
Complex Ions ◽  
Cobaltous Chloride ◽  
Iodide Ions ◽  
Effect Of Pressure ◽  
Iodide Ion ◽  
Complex Ion

The effect of pressure on the formation of complex ions in solutions of cobaltous chloride and in solutions containing iodine and iodide has been shown to be in qualitative agreement with a theory (Buchanan and Hamann 1953) attributing these effects primarily to changes in the free energy of salvation of the ions. The dissociation constant of tri-iodide ions in water at 22 �C has been shown to decrease from 1.6 x 10-3 mol kg-1 at atmospheric pressure to 1.2 x mol kg-1 at 1500 atm. The enthalpy of dissociation of the tri-iodide ion was found to be approximately -5 kcal mol-1 and to be little affected by a pressure of 1500 atm.

COMPLEX MANGANESE PERIODATES

1960 ◽  
Vol 38 (8) ◽  
pp. 1291-1299 ◽  
Author(s):  
M. W. Lister ◽  
Y. Yoshino
Keyword(s):  
Unpaired Electron ◽  
Magnetic Moment ◽  
Absorption Maximum ◽  
Ferrous Ions ◽  
Complex Ions ◽  
Acid Base ◽  
Iodide Ions ◽  
Reaction Proceeds ◽  
Kinetics Of ◽  
Complex Ion

The preparation of complex periodatomanganates, from manganous salts reacting with sodium (or potassium) hypochlorite and periodate, is described. The products were Na7H4Mn(IO6)3.17H2O and K7H4Mn(IO6)3.8H2O. The manganese was shown to be tetravalent from its redox equivalent in its reaction with iodide and with ferrous ions, and from its magnetic moment, which was 3.87 Bohr magnetons, corresponding to three unpaired electron spins. The ion has an absorption maximum at 483 mμ. Rather complicated pH curves were found for this compound in acid-base titrations. The complex ion decomposes slowly to permanganate and iodate; the kinetics of this reaction have been measured, and a possible mechanism has been suggested. The reaction proceeds in several steps by way of simpler complex ions. The same applies to the reaction between iodide ions and the complex ions when the pH is about 9.

Viscosity of Dimethyl Sulfoxide + 1,4 Dimethylbenzene System

2008 ◽  
Vol 59 (1) ◽  
pp. 45-48
Author(s):  
Oana Ciocirlan ◽  
Olga Iulian
Keyword(s):  
Free Energy ◽  
Dimethyl Sulfoxide ◽  
Atmospheric Pressure ◽  
Entire Range ◽  
Polynomial Equation ◽  
Energy Of Activation ◽  
Excess Gibbs Free Energy ◽  
Experimental Measurements ◽  
Gibbs Energy Of Activation ◽  
Free Energy Of Activation

This paper reports the viscosities measurements for the binary system dimethyl sulfoxide + 1,4-dimethylbenzene over the entire range of mole fraction at 298.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The experimental viscosities were correlated with the equations of Grunberg-Nissan, Katti-Chaudhri, Hind, Soliman and McAllister; the adjustable binary parameters have been obtained. The excess Gibbs energy of activation of viscous flow (G*E) has been calculated from the experimental measurements and the results were fitted to Redlich-Kister polynomial equation. The obtained negative excess Gibbs free energy of activation and negative Grunberg-Nissan interaction parameter are discussed in structural and interactional terms.

A ratiometric optical strategy for bromide and iodide ion sensing based on target-induced competitive coordination of a metal–organic nanosystem

2020 ◽  
Vol 8 (33) ◽  
pp. 11517-11524
Author(s):  
Yu Zhu Fan ◽  
Lei Han ◽  
Shi Gang Liu ◽  
Ying Zhang ◽  
Hong Qun Luo ◽  
...  
Keyword(s):  
Self Assembly ◽  
Iodide Ions ◽  
Ratiometric Sensing ◽  
Ion Sensing ◽  
Coordination Bonding ◽  
Iodide Ion ◽  
Competitive Coordination ◽  
Metal Organic

A metal–organic nanosystem constructed via coordination bonding-induced self-assembly is used for fluorescence and scattering ratiometric sensing of bromide and iodide ions.

scholarly journals Studies on Erythropoiesis

Blood ◽  
1958 ◽  
Vol 13 (1) ◽  
pp. 55-60 ◽  
Author(s):  
EUGENE GOLDWASSER ◽  
LEON O. JACOBSON ◽  
WALTER FRIED ◽  
LOUIS F. PLZAK
Keyword(s):  
Metal Ions ◽  
High Titer ◽  
Active Material ◽  
Cobaltous Chloride ◽  
Complex Ion

Abstract It has been shown that plasma from animals that have been injected with cobaltous chloride rapidly develops a high titer of erythropoietin. The gross properities of the active material appear to be the same from cobalt-treated as from phenylhydrazine-treated animals. Other metal ions and a complex ion have been studied as stimulants for erythropoietin formation; none was as effective as cobaltous ion with the exception of cobaltic hexamine.

Solubility and Complex-Ion Equilibria

2021 ◽  
pp. 313-324
Author(s):  
Christopher O. Oriakhi
Keyword(s):  
Metal Complexes ◽  
Solubility Product ◽  
Formation Constants ◽  
Aqueous Systems ◽  
Complex Ions ◽  
Ionic Compounds ◽  
Molar Solubility ◽  
Solubility Product Constant ◽  
Complex Ion

Solubility and Complex-Ion Equilibria broadens the previous chapter’s coverage of equilibria to include aqueous systems containing two or more solutes of slightly soluble ionic compounds and the formation of metal complexes in solution. Solubility equilibria which allow quantitative predictions of how much of a compound will dissolve under given conditions are covered. The meaning of the solubility product constant (K sp) and how to calculate it from molar solubility values is presented. Also discussed is determination of molar solubility from K sp. Calculations demonstrate how to predict the formation of a precipitate by comparing the ion product or solubility quotient (Q) with K sp. Formation constants of complex ions and calculations involving complex ion equilibria are explained.

Enantiomerization of Pendant-Arm Triaza Macrocyclic Lithium(I) and Sodium(I) Complex Ions

1997 ◽  
Vol 50 (8) ◽  
pp. 853 ◽  
Author(s):  
Sonya L. Whitbread ◽  
Jennifer M. Weeks ◽  
Peter Valente ◽  
Mark A. Buntine ◽  
Stephen F. Lincoln ◽  
...  
Keyword(s):  
Stability Constant ◽  
Alkali Metal ◽  
Variable Temperature ◽  
Molecular Orbital Calculations ◽  
Complex Ions ◽  
Pendant Arm ◽  
Alkali Metal Complex ◽  
Ion Stability ◽  
Trigonal Prismatic ◽  
Complex Ion

The first reported enantiomerization of six-coordinate alkali metal complex ions, represented by 1,4,7-tris(2-hydroxyethyl)-1,4,7-triazacyclononanelithium(I) and its sodium(I) analogue in methanol, has been characterized by variable-temperature 13C{1H} n.m.r. spectroscopy. The respective kinetic parameters are: k = (1·11 ± 0·05) × 106 and (2·27 ± 0·09) × 105 s-1 at 298·2 K, ΔH = 27·2 ± 0·3 and 21·7±0·2 kJ mol-1, and ΔS = –36·3 ± 1·3 and –69·6±1·2 J K-1 mol-1. Molecular orbital calculations show that these enantiomers have distorted trigonal prismatic structures consistent with the interpretation of the n.m.r. spectra. For the Li+, Na+, K+, Rb+ and Cs+ complex ions log(K/dm3 mol−1) = 3·13±0·09, 3·52±0·05, 3·23±0·05, 2·78±0·10 and 2·47±0·08, respectively, at 298·2 K and I = 0·05 mol dm-3 (NEt4 ClO4) in methanol, where K is the complex ion stability constant.

scholarly journals THE EFFECT OF SALTS ON THE IONISATION OF GELATIN

1930 ◽  
Vol 14 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Kenneth V. Thimann
Keyword(s):  
Sodium Chloride ◽  
Salt Concentration ◽  
Acid Solutions ◽  
Ionic Structure ◽  
Complex Ions ◽  
Similar Action ◽  
Ion Formation ◽  
Copper Chlorides ◽  
Positive Ion ◽  
Complex Ion

The effect of the addition of sodium chloride to gelatin solutions is shown from the Donnan relationship to increase the ionisation of the gelatin, the increase produced in acid solutions reaching a maximum at about 1/1000 molar salt concentration. This effect is attributed to the formation of complex ions. From the similar action of calcium and copper chlorides the effective combining power of gelatin for complex positive ion formation is deduced. The bearing of complex ion formation on the zwitter-ionic structure and solubility phenomena of proteins is pointed out.

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