Protodemercuration of organomercuric chlorides. I. Aromatic mercuric chlorides

1965 ◽  
Vol 18 (10) ◽  
pp. 1507 ◽  
Author(s):  
RD Brown ◽  
AS Buchanan ◽  
AA Humffray
Keyword(s):  
Hydrochloric Acid ◽  
Correlation Coefficient ◽  
Chloride Ion ◽  
Zero Order ◽  
Hydrogen Ion ◽  
First Order ◽  
Phenylmercuric Chloride ◽  
Kinetics Of

The kinetics of protodemercuration, or displacement of the HgCl group by hydrogen, have been measured for phenylmercuric chloride, and also for its meta and para methyl-, chloro-, and methoxy-substituted derivatives. The reactions of the compounds with aqueous alcoholic hydrochloric acid were first order in RHgC1, first order in hydrogen ion, and zero order in chloride ion. At 70" the relative rates, which were largely determined by entropy factors, were: phenyl, 1; p-tolyl, 7; m-tolyl, 2.4; p-chlorophenyl, 0.67; m-chlorophenyl, 0.26; p-methoxy, 150; m-methoxy, 0.71. A plot of log k against σ+ gives a ρ value of -2.44, and correlation coefficient of 0.986.

Protodemercuration of organomercuric chlorides. II. Heterocyclic mercuric chlorides

1965 ◽  
Vol 18 (10) ◽  
pp. 1513 ◽  
Author(s):  
RD Brown ◽  
AS Buchanan ◽  
AA Humffray
Keyword(s):  
Chloride Ion ◽  
Ion Pair ◽  
Zero Order ◽  
Hydrogen Ion ◽  
First Order ◽  
Entropy Effects ◽  
Kinetics Of ◽  
Complex Anions ◽  
Dominant Influence ◽  
Electron Effects

The kinetics of protodemercuration, or displacement of the HgCl group by hydrogen, have been measured for 2- and 3-furyl, 2-thienyl, and 2-selenophenylmercuric chlorides. The reactions of these compounds with aqueous alcoholic hydrochloric acid were first order in hydrogen ion, first order in RHgC1, and zero order in chloride ion, when the latter was present at concentrations less than 0.1M. At 70�, the relative rates were: 3-furyl, 1; 2-furyl, 27; 2-thienyl, 11; 2-seleno- phenyl, 25. At higher chloride concentrations, the rate increases; this is discussed in terms of formation of complex anions of the type RHgCl32- and in terms of H+Cl- ion pair attack. The dominant influence of entropy effects in the case of furan compounds emphasizes the danger of trying to account for observed relative rates in terms of π-electron effects alone.

KINETICS AND MECHANISM OF COMPLEX FORMATION BETWEEN ETHYLENE AND RUTHENIUM(II) CHLORIDE IN AQUEOUS SOLUTION

1966 ◽  
Vol 44 (4) ◽  
pp. 495-500 ◽  
Author(s):  
Jack Halpern ◽  
Brian R. James
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Complex Formation ◽  
Acid Solution ◽  
Chloride Ion ◽  
Initial Step ◽  
Hydrogen Ion ◽  
Π Complex ◽  
Kinetics Of ◽  
Aqueous Hydrochloric Acid Solution

The formation of a 1:1 π-complex between ethylene and ruthenium(II) in aqueous hydrochloric acid solution is described. The kinetics of the reaction were examined over a range of temperatures and of concentrations of ruthenium(II), ethylene, hydrogen ion, and chloride ion. The results suggest that complex formation proceeds through a stepwise (SN1) mechanism in which the initial step involves the dissociation of a chlororuthenate(II) complex.

Kinetics of catalytic reduction of nitrogen oxide by carbon monoxide on CuO/Al2O3 catalyst

1983 ◽  
Vol 48 (11) ◽  
pp. 3202-3208 ◽  
Author(s):  
Zdeněk Musil ◽  
Vladimír Pour
Keyword(s):  
Carbon Monoxide ◽  
Nitrogen Oxide ◽  
Rate Equation ◽  
Catalytic Reduction ◽  
Zero Order ◽  
Spectroscopic Measurements ◽  
First Order ◽  
Ir Spectroscopic ◽  
Kinetics Of ◽  
Al2o3 Catalyst

The kinetics of the reduction of nitrogen oxide by carbon monoxide on CuO/Al2O3 catalyst (8.36 mass % CuO) were determined at temperatures between 413 and 473 K. The reaction was found to be first order in NO and zero order in CO. The observed kinetics are consistent with a rate equation derived from a mechanism proposed on the basis of IR spectroscopic measurements.

Supercritical Fluid Deposition of Ruthenium Thin Films: A Kinetic Study

2007 ◽  
Vol 992 ◽  
Author(s):  
Christos F. Karanikas ◽  
James J. Watkins
Keyword(s):  
Thin Films ◽  
Growth Rate ◽  
Deposition Temperature ◽  
Zero Order ◽  
Measurable Effect ◽  
Deposition Rates ◽  
Reaction Pressure ◽  
Deposition Kinetics ◽  
First Order ◽  
Kinetics Of

AbstractThe kinetics of the deposition of ruthenium thin films from the hydrogen assisted reduction of bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclooctadiene)ruthenium(II), [Ru(tmhd)2cod], in supercritical carbon dioxide was studied in order to develop a rate expression for the growth rate as well as to determine a mechanism for the process. The deposition temperature was varied from 240°C to 280°C and the apparent activation energy was 45.3 kJ/mol. Deposition rates up to 30 nm/min were attained. The deposition rate dependence on precursor concentrations between 0 and 0.2 wt. % was studied at 260°C with excess hydrogen and revealed first order deposition kinetics with respect to precursor at concentrations lower then 0.06 wt. % and zero order dependence at concentrations above 0.06 wt. %. The effect of reaction pressure on the growth rate was studied at a constant reaction temperature of 260°C and pressures between 159 bar to 200 bar and found to have no measurable effect on the growth rate.

scholarly journals Reactivity of Phenol and Aniline towards Quinolinium Chloro Chromate: A Comparative Oxidation Kinetic Study

2015 ◽  
Vol 59 ◽  
pp. 81-92
Author(s):  
Seplapatty Kalimuthu Periyasamy ◽  
H. Satham Hussain ◽  
R. Manikandan
Keyword(s):  
Oxidation Kinetic ◽  
Activation Parameters ◽  
Dipole Interaction ◽  
Reaction Rates ◽  
Hydrogen Ion ◽  
Aqueous Acetic Acid ◽  
Acetic Acid Medium ◽  
First Order ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of Oxidation of Phenol and aniline by quinolinium Chlorochromate (QCC) in aqueous acetic acid medium leads to the formation of quinone and azobenzene respectively. The reactions are first order with respect to both Phenol and aniline. The reaction is first order with respect to quinolinium chlorochromate (QCC) and is catalyzed by hydrogen ion. The hydrogen-ion dependence has the form: kobs = a+b [H+]. The rate of oxidation decreases with increasing dielectric constant of solvent, indicating the presence of an ion-dipole interaction. The reaction does not induced the polymerization of acrylonitrile. The retardation of the rate by the addition of Mn2+ ions confirms that a two electron transfer process is involved in the reaction. The reaction rates have been determined at different temperatures and the activation parameters have been calculated. From the above observations kinetic results a probable mechanism have been proposed.

Kinetics of aquation of the fluoropentaamminecobalt(III) ion

1970 ◽  
Vol 48 (7) ◽  
pp. 1054-1058 ◽  
Author(s):  
T. W. Swaddle ◽  
W. E. Jones
Keyword(s):  
Ionic Strength ◽  
Rate Coefficient ◽  
Hydrogen Ion ◽  
Fluoride Ion ◽  
Kcal Mole ◽  
First Order ◽  
Order Rate ◽  
Relationship Of ◽  
The Relationship ◽  
Kinetics Of

The kinetics of the hydrogen-ion-independent pathway for the replacement of fluoride in aqueous (NH3)5CoF2+ by H2O have been reinvestigated using a specific fluoride-ion electrode, with due regard for the concomitant autocatalytic loss of the ammine ligands. In perchlorate media of ionic strength 0.1 M, the first-order rate coefficient is 1.22 × 10−6 s−1 at 45°, and the kinetics are represented by ΔH* = 24.4 kcal mole−1 and ΔS* = −9 cal deg−1 mole−1 over the range 35–75° at least. The relationship of these data to those for the aquation of other species of the type ML5Xn+ is discussed.

Pseudo-Homogenous Kinetics Model for the Synthesis of Dimethyl Carbonate from Urea and Methanol with Heterogeneous Catalyst

2011 ◽  
Vol 233-235 ◽  
pp. 481-486
Author(s):  
Wen Bo Zhao ◽  
Ning Zhao ◽  
Fu Kui Xiao ◽  
Wei Wei
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Dimethyl Carbonate ◽  
Side Reaction ◽  
Order Reaction ◽  
Zero Order ◽  
Kinetics Model ◽  
First Order ◽  
Zero Order Reaction ◽  
Kinetics Of

The synthesis of dimethyl carbonate (DMC) from urea and methanol includes two main reactions: one amino of urea is substituted by methoxy to produce the intermediate methyl carbamate (MC) which further converts to DMC via reaction with methanol again. In a stainless steel autoclave, the kinetics of these reactions was separately investigated without catalyst and with Zn-containing catalyst. Without catalyst, for the first reaction, the reaction kinetics can be described as first order with respect to the concentrations of methanol and methyl carbamate (MC), respectively. For the second reaction, the results exhibit characteristics of zero-order reaction. Over Zn-containing catalyst, the first reaction is neglected in the kinetics model since its rate is much faster than second reaction. After the optimization of reaction condition, the macro-kinetic parameters of the second reaction are obtained by fitting the experimental data to a pseudo-homogenous model, in which a side reaction of DMC synthesis is incorporated since it decreases the yield of DMC drastically at high temperature. The activation energy of the reaction from MC to DMC is 104 KJ/mol while that of the side reaction of DMC is 135 KJ/mol.

Parameters Effect on Photocatalytic Reduction Kinetics of Bromate in Aqueous Dispersion of TiO2

2013 ◽  
Vol 779-780 ◽  
pp. 1658-1665
Author(s):  
Rong Shu Zhu ◽  
Fei Tian ◽  
Ling Ling Zhang ◽  
Ling Min Yu
Keyword(s):  
Aqueous Dispersion ◽  
Zero Order ◽  
Photocatalytic Reduction ◽  
Reduction Kinetics ◽  
First Order ◽  
First Order Kinetics ◽  
Zero Order Kinetics ◽  
Experimental Parameters ◽  
Pseudo First Order ◽  
Kinetics Of

This paper studied the photocatalytic reduction kinetics of bromate in aqueous dispersion of TiO2 and investigated the effects of experimental parameters, including initial concentration of BrO3-, pH, TiO2 dosage, anion and cation. The results indicate that the process of photocatalytic reduction of bromate follows a zero-order kinetics. In all the investigated experimental parameters, the initial bromate concentration, pH and anion have great effect on the photocatalytic reduction kinetics. The processes of photocatalytic reduction of bromate show the pseudo first-order kinetics at initial bromate concentration of 0.39 μmolL-1, pH=5.0, or in presence of HCO3-/CO32-, NO3-, SO42-, respectively.

Kinetics of the Heterogeneous Ozonation of Nitrated Phenols

1992 ◽  
Vol 26 (1-2) ◽  
pp. 169-180 ◽  
Author(s):  
J. P. Gould ◽  
G. V. Ulirsch
Keyword(s):  
Mass Transfer ◽  
Rate Constants ◽  
Chemical Structure ◽  
Process Analysis ◽  
Qsar Model ◽  
Zero Order ◽  
Transfer Coefficients ◽  
First Order ◽  
Kinetics Of ◽  
Phenolic Concentration

The kinetics of the heterogeneous ozonation of phenol and 27 nitrophenols representing a wide array of functional groups have been studied. In the systems examined, the process has been found to be zero order with respect to phenolic concentration which indicates mass transfer as the prime control on the process. Analysis of the first order rate constants has permitted computation of overall mass transfer coefficients for all compounds. The coefficients were sixty percent lower than the kLa values measured by others in water and showed very little variation regardless of chemical structure of the phenol. Efforts at development of a QSAR model for the kinetics were fruitless.

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