scholarly journals Equilibrium quotient for the isomerization of bisulfite ion from HSO3- to SO3H-

1986 ◽  
Vol 25 (14) ◽  
pp. 2414-2417 ◽  
Author(s):  
David A. Horner ◽  
Robert E. Connick
Keyword(s):  
Equilibrium Quotient

Aluminum(III) Coordination to Hydroxy Carboxylates: the Influence of Hydroxy Substituents Enabling Tridentate Binding

1994 ◽  
Vol 47 (11) ◽  
pp. 2023 ◽  
Author(s):  
WM Best ◽  
JM Harrowfield ◽  
TM Shand ◽  
RV Stick
Keyword(s):  
Aqueous Media ◽  
Close Similarity ◽  
Equilibrium Quotient

Potentiometric evalution of the interaction between aluminium(III) and the hydroxy carboxylates 3-deoxy-D-ribo-hexonate (L1H) and 2,5-dihydroxypentanoate (L2H) provided evidence for the formation of 1:1 complexes only, though with the ligand being present in singly, doubly and quadruply deprotonated forms in the hexonate complexes, and in singly, doubly and triply deprotonated forms in those of the pentanoate. At 298 K in aqueous media, I = 0.1 ( NaCl ), equilibrium quotient values obtained through use of the programs PKAS and BEST were: -log([(L1)-][H+]/[L1H])(or pKa(L1H))= 3.58�0.03 log([(AlL1)2+]/[Al3+][(L1)-])=1.97�0.03 log([(AlH-1L1)+][H+]/[(AlL1)2+])= -2.83�0.05 log([(AlH-3L1)-][H+]2/[(AlH-1L1)+])= -9.17�0.08 -log([(L2)-][H+]/[L2H])(or pKa(L2H))= 3.92�0.03 log([(AlL2)2+]/[Al3+][(L2)-])= 2.04�0.03 log([(AlH-1L2)+][H+]/[AlL2)2+])= -3.14�0.06 log([AlH-2L2][H+]/[(AlH-1L2)+])= -2.25�0.09 The very close similarity of the results for 3-deoxy-D-ribo-hexonate (3-deoxygluconate) and those known for D(+)-gluconate has led to the suggestion that the complexes of the quadruply deprotonated ligands may involve trialkoxo coordination through the C1, C5 and C6 substituents.

LINEAR FREE ENERGY RELATIONSHIPS CONCERNING EQUILIBRIA IN MODERATELY CONCENTRATED MINERAL ACIDS: A SIMPLE METHOD FOR ESTIMATING pK's OF WEAK BASES

1966 ◽  
Vol 44 (16) ◽  
pp. 1899-1916 ◽  
Author(s):  
J. F. Bunnett ◽  
Fredric P. Olsen
Keyword(s):  
Free Energy ◽  
Acid Concentration ◽  
Standard Form ◽  
Acidity Function ◽  
Linear Free Energy Relationships ◽  
Simple Method ◽  
Linear Free Energy ◽  
Equilibrium Quotient ◽  
Mineral Acids ◽  
Energy Relationships

Linear relationships exist between the logarithms of equilibrium quotients, [SH+]/[S][H+], of diverse bases as they vary with acid concentration in moderately concentrated mineral acids. For purposes of formulating these linear free energy relationships in standard form, the equilibrium quotient for protonation of a hypothetical aromatic primary amine of pKa zero has been chosen as horizontal coordinate; this is given by (−H0 − log [H+]). Log ([SH+]/[S]) + H0 is plotted against (H0 + log [H+]). The slope, [Formula: see text] of the linear plot is a parameter which characterizes the response of the equilibrium quotient to changing acid concentration. The intercept represents the thermodynamic pKa of the base. This constitutes a general method for estimating the pKa of any base which undergoes protonation in moderately concentrated mineral acid, with reference to the single acidity function, H0. For bases of diverse type, pK's estimated by this method are in good agreement with those estimated by the acidity function method. Use of the new correlation procedure as a check on the validity of several acidity functions and its application to equilibria not involving proton gain or loss are also discussed.

CHELATION STUDY OF COPPER (II): FULVIC ACID SYSTEM

1973 ◽  
Vol 53 (4) ◽  
pp. 377-382 ◽  
Author(s):  
VENGHUOT CHEAM
Keyword(s):  
Fulvic Acid ◽  
Mole Fraction ◽  
Sodium Nitrate ◽  
Direct Approach ◽  
Acid System ◽  
Selective Electrode ◽  
Cupric Ion ◽  
Equilibrium Quotient ◽  
Chelation Reaction ◽  
Nitrate Solutions

The chelation reaction between Cu (II) and fulvic acid has been investigated using a relatively new direct approach — that of titration with a cupric ion-selective electrode. The results of different investigators are in fair agreement with each other if they are interpreted in terms of both pH and mole fraction of reactants. In 0.1 M sodium nitrate solutions with a copper mole fraction equal to 0.5 ± 0.2, the equilibrium quotient at 25 C and pH 3 was found to be 2.2 ± 0.1.

scholarly journals Revaluation of equilibrium quotient between titanium ions and metallic titanium in NaCl–KCl equimolar molten salt

2011 ◽  
Vol 509 (18) ◽  
pp. 5477-5482 ◽  
Author(s):  
Hidehiro Sekimoto ◽  
Yoshitaro Nose ◽  
Tetsuya Uda ◽  
Akihiro Uehara ◽  
Hajimu Yamana ◽  
...  
Keyword(s):  
Molten Salt ◽  
Metallic Titanium ◽  
Equilibrium Quotient

ChemInform Abstract: Equilibrium Quotient for the Isomerization of Bisulfite Ion from HSO3-to SO3H-

1986 ◽  
Vol 17 (43) ◽  
Author(s):  
D. A. HORNER ◽  
R. E. CONNICK
Keyword(s):  
Equilibrium Quotient

Dephosphorization Ability Estimation of FetO-Rich Demanganization Slag during Hot Metal Pre-Treatment

2012 ◽  
Vol 560-561 ◽  
pp. 1027-1034
Author(s):  
Cheng Yi Zhu ◽  
Jun Liu ◽  
Guang Qiang Li ◽  
Zhao Ping Chen
Keyword(s):  
Phosphorus Content ◽  
Hot Metal ◽  
Phosphorus Distribution ◽  
Equilibrium Quotient ◽  
Multiple Regression Method ◽  
Solid Iron ◽  
Thermodynamic Conditions ◽  
Pre Treatment ◽  
Phosphorus Distribution Ratio ◽  
Pure Argon Atmosphere

In order to find out the optimum thermodynamic conditions for hot metal dephosphorization and predict phosphorus content after demanganization pretreatment, thermodynamic equilibrium experiments between CaO-FetO-SiO2-MnO-P2O5 slag and silver/solid iron were carried out in an iron crucible at different temperature under pure argon atmosphere in an electric resistant furnace. The results indicate that phosphorus distribution ratios increase with an increase of basicity in the slag at the experiment temperature, and then they decrease with an increase of basicity at 1573K and 1623K. The phosphorus distribution ratios decrease with an increase of FetO content in the slag at 1573K, while they increase with an increase of FetO content in the slag and then decrease with an increase of FetO content in the slag at 1623K. The results indicate that the maximum phosphorus distribution ratio between slag and hot metal is 92.4 when basicity of the slag is 1.7 and FetO content in slag is 49.75 mass% at 1623K, and the correspondent phosphorus content in the carbon saturated iron is 0.019mass%. Dephosphorization is easier under low temperature. The equilibrium quotient of phosphorus obtained in the present work is formulated as a function of slag compositions and temperature using the multiple regression method which is used to predict phosphorus content equilibrium with the demanganization slag and optimum conditions needed for ideal phosphorus contents in demanganization pretreatment.

Evaluation of Unbonded O—H Groups for HDO in Liquid D2O from Infrared Absorptivity Measurements

1972 ◽  
Vol 50 (11) ◽  
pp. 1655-1665 ◽  
Author(s):  
E. C. W. Clarke ◽  
D. N. Glew
Keyword(s):  
Temperature Dependence ◽  
Equilibrium Constant ◽  
Standard Enthalpy ◽  
Liquid State ◽  
Low Temperatures ◽  
Enthalpy Change ◽  
Weak Band ◽  
Equilibrium Quotient ◽  
Standard Enthalpy Change

Wyss and Falk's infrared absorptivities between 10 and 85 °C for HDO in liquid D2O in the fundamental O—H stretch region have been analyzed numerically and show a statistically significant weak band near 3600 cm−1 at each temperature. This band, the Raman analog of which was reported earlier, confirms the presence of HDO species with unbonded O—H groups in the liquid state. The percentage of HDO species with un-bonded O—H groups is found to be 4.6, 6.1, 10.1, and 11.9, respectively, at 10, 35, 60, and 85 °C.The four predominant HDO species in equilibrium at low temperatures are denned together with their equilibrium constant for the [Formula: see text] bond-rupturing process. A standard enthalpy change of ΔH° = 6800 ± 1100 cal is found for the rupture of one mole of [Formula: see text] bonds. This is in contrast with the apparent enthalpy change of 2900 ± 500 cal, as usually derived from the temperature dependence of the equilibrium quotient. Approximate mole fractions for each of twelve differently bonded HDO species are derived from a model for random H- and D-bond statistics. Results show that the four predominant HDO species give a full interpretation of the absorptivities at 10, 35, and 60 °C but that additional minor species contribute slightly to the absorptivity at 85 °C.

scholarly journals Spectrophotometric Study of Adduct Formation Between [Co(Salen)PPh3]ClO4.H2O and [Co(7,7'-Dimethylsalen)PPh3]ClO4.H2O with Amines Donors in Acetonitrile

2010 ◽  
Vol 7 (4) ◽  
pp. 1421-1425
Author(s):  
Mahmood Niad ◽  
Khosro Mohammadi ◽  
Mozaffar Asadi
Keyword(s):  
Schiff Base ◽  
Ionic Strength ◽  
Room Temperature ◽  
Sodium Perchlorate ◽  
Spectrophotometric Study ◽  
Adduct Formation ◽  
Schiff Base Complexes ◽  
Constant Ionic Strength ◽  
Equilibrium Quotient ◽  
Donor And Acceptor

The equilibrium quotient of the adduct formation of [Co(Salen)PPh3]ClO4.H2O and [Co(7,7'-dimethylSalen)PPh3]ClO4.H2O, as acceptor with amines donors are studied by spectrophotometer. Thermodynamics of these pentacoordinate cobalt(III) Schiff-base complexes have been examined withn-butylamine,sec-butylamine,tert-butylamine, benzylamine and diethylamine in constant ionic strength of 0.1 M sodium perchlorate and acetonitrile solvent at room temperature. We aimed to investigate the effects of different electronic and steric situations of donor and acceptor by comparing their equilibrium quotient for any adduct.

AN ULTRASONIC STUDY OF SOME OF THE COMPLEXING REACTIONS OF CHLORIDE WITH CADMIUM ION

1964 ◽  
Vol 42 (5) ◽  
pp. 1186-1197 ◽  
Author(s):  
J. P. Valleau ◽  
S. J. Turner
Keyword(s):  
Activation Energy ◽  
Dissociation Rate ◽  
Volume Changes ◽  
Cadmium Ion ◽  
Pulse Technique ◽  
Cadmium Ions ◽  
Equilibrium Quotient ◽  
Ultrasonic Determination ◽  
Dissociation Rate Constants

The ultrasonic absorptions of 0.25 M aqueous solutions of cadmium ions, containing various amounts of hydrochloric acid, have been measured by a pulse technique between 13 and 143 Mc/second at 16°, 25°, and 35 °C. A relaxation occurs in this region, and it has been interpreted in terms of the interacting association reactions[Formula: see text]An ultrasonic determination of the equilibrium quotient of the second of these reactions has been made, and the association and dissociation rate constants are reported for both reactions. In addition, the volume changes, ΔV, in the two reactions have been estimated, along with the activation energy for the dissociation of CdCl3−. The analysis breaks down at low ligand concentrations, and this is ascribed to the influence of a third interacting reaction.

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