ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFluctuations and stirring rate effects in the chlorite-thiosulfate reactionIstvan Nagypal Irving R. EpsteinCite this: J. Phys. Chem. 1986, 90, 23, 6285–6292Publication Date (Print):November 1, 1986Publication History Published online1 May 2002Published inissue 1 November 1986https://pubs.acs.org/doi/10.1021/j100281a044https://doi.org/10.1021/j100281a044research-articleACS PublicationsRequest reuse permissionsArticle...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGravity-induced anisotropies in chemical wavesIstvan. Nagypal, Gyorgy. Bazsa, and Irving R. EpsteinCite this: J. Am. Chem. Soc. 1986, 108, 13, 3635–3640Publication Date (Print):June 1, 1986Publication History Published online1 May 2002Published inissue 1 June 1986https://pubs.acs.org/doi/10.1021/ja00273a015https://doi.org/10.1021/ja00273a015research-articleACS PublicationsRequest reuse permissionsArticle Views173Altmetric-Citations126LEARN ABOUT...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSystematic design of chemical oscillators. 60. Kinetics and mechanism the reaction between chlorite ion hypochlorous acidGabor. Peintler, Istvan. Nagypal, Irving R. EpsteinCite this: J. Phys. Chem. 1990, 94, 7, 2954–2958Publication Date (Print):April 5, 1990Publication History Published online1 May 2002Published inissue 5 April 1990https://pubs.acs.org/doi/10.1021/j100370a040https://doi.org/10.1021/j100370a040research-articleACS PublicationsRequest...

Autocatalytic systems are sometimes designated as clock reactions or that exhibit behavior. To resolve the recent dispute over term reaction, we describe a new approach to classify featuring behavior into three distinct groups: substrate-depletive reactions, autocatalysis-driven and have pseudo Many of well-known classical recently discovered can conveniently be put these categories. We also provide convincing argument for classifying some autocatalytic processes but it does not necessarily...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAn algorithm for the design of propagating acidity frontsLajos Szirovicza, Istvan Nagypal, and Endre BogaCite this: J. Am. Chem. Soc. 1989, 111, 8, 2842–2845Publication Date (Print):April 1, 1989Publication History Published online1 May 2002Published inissue 1 April 1989https://pubs.acs.org/doi/10.1021/ja00190a016https://doi.org/10.1021/ja00190a016research-articleACS PublicationsRequest reuse permissionsArticle Views170Altmetric-Citations47LEARN...

For many, especially complex, systems, modern spectroscopic measurements can be generated as large experimental data sets in matrix form. We report a new algorithm for the application of rank analysis to extract significant information from these matrixes. The may used detect and remove erroneous rows and/or columns matrixes monitor most along sets. A method determining number absorbing species concept treatment errors are presented. is illustrated on real examples.

pH Titrimetry and calorimetry have been used to determine the stoicheiometries, stability constants, enthalpies entropies of formation complexes formed in systems copper(II) with glycylglycine, glycyl-DL-α-alanine, DL-α-alanylglycine, DL-α-alanyl-DL-α-alanine, at ionic strength I= 0.2 mol dm–3 KCl 25 °C. There is no possibility titrimetric indication [CuL2] [CuL2H–2]2–(L = dipeptide anion H2N–CHR–CO–NH–CHR′–CO2–) these equilibrium systems, even when their maximum concentration 10–15%. The...

The kinetics of decomposition aqueous chlorous acid has been reinvestigated at pH 0.7−1.9, ionic strength 1.0 M (HSO4-/SO42-), and temperature 25.0 ± 0.1 °C. Optical absorbances were collected in the 240−450 nm wavelength range for up to ∼90% time series lasting as long 2 days. number absorbing species was investigated by matrix rank analysis; no intermediate formed significant concentration during decomposition. Of many mechanistic models tested, one that fit best included following...

The chlorite−tetrathionate reaction has been studied spectrophotometrically in the pH range of 4.65−5.35 at T = 25.0 ± 0.2 °C with an ionic strength 0.5 M, adjusted sodium acetate as a buffer component. is unique that it demonstrates autocatalysis respect to hydrogen and chloride ion products key intermediate, HOCl. thermodynamically most-favorable stoichiometry, 2S4O62- + 7Cl 6H2O → 8SO42- 7Cl- 12H+, not found. Under our experimental conditions, chlorine dioxide, chlorate ion, or both are...

The autocatalytic reaction between chlorite and iodide ions in a closed system is clock reaction, showing sudden appearance of brown I2 followed by rapid disappearance the color. Under certain conditions, time displays striking irreproducibility. This stochastic behavior studied potentiometrically spectrophotometrically as function initial [I− ], stirring rate solution volume. results imply that irreproducibility an inherent feature generated fluctuations after it ‘‘well mixed.’’ key...

The effect of chloride ion on the chlorine dioxide formation in ClO 2 (-)-HOCl reaction was studied by following .ClO concentration spectrophotometrically at pH 5-6 0.5 M sodium acetate. On basis earlier experimental data collected without initially added and new experiments, kinetic model modified extended to interpret two series experiments together. It found that significantly increases initial rate formation. At same time, yield is increased HOCl but decreased (-) excess increase...

A series of isotropic EPR spectra recorded at various concentrations and pH (in the range 2-12) on equilibrium systems containing copper(II) diglycine, triglycine, or tetraglycine were analyzed. purely mathematical method, matrix rank analysis gave number independent EPR-active species. Two-dimensional evaluation then resulted in formation constants magnetic parameters 14 metal complexes (including microspecies) each system. The paramagnetic species formed with ligand are as follows: Cu(2+)...

The initial rate of formation chlorine dioxide in the chlorite−tetrathionate reaction changes an unusual fashion. formal kinetic order both reactants varies over a very wide range. Moreover, chlorite ion behaves not just as simple reactant, but also self-inhibitor. A five-step scheme, derived from eight-step mechanism, is proposed which autocatalytic HOCl plays central role accounting for this behavior.

The sulfite−chlorine dioxide reaction was studied by stopped-flow method at I = 0.5 M and 25.0 ± 0.1 °C in a slightly acidic medium. stoichiometry found to be 2 SO32- + 2·ClO2 H2O → 2SO42 - Cl- ClO3- 2H+ ·ClO2 excess 6SO32- S2O62- 4SO42- 2Cl- total sulfite ([S(IV)] [H2SO3] [HSO3-] [SO32-]). A nine-step model with four fitted kinetic parameters is suggested which the proposed adduct ·SO3ClO22- plays significant role. pH-dependence of traces indicates that reacts much faster than HSO3- does.

The reaction between thiosulfate and chlorine dioxide in slightly alkaline medium has been studied by stopped-flow techniques. cannot be under pseudo-first-order condition, thus a new approach based on the improved calibration use of spectrophotometers was applied. starts with irreversible formation •S2O3ClO22- radical. main path produces tetrathionate chlorite through light absorbing radical (•S4O63-). Any reactant present excess modifies 1:1 stoichiometry, sulfate as well chloride ions are...

When subject to illumination, tetrathionate ion decomposes in an oscillatory fashion with a period of about 1 h yield products identified as colloidal sulfur and trithionate ion. This system represents the first experimental example stirred, batch photochemical oscillator. A simple model consisting four reaction steps adjustable rate parameters gives good agreement observed behavior.