Belousov-Zhabotinskii oscillation reaction with glyceraldehyde

An oscillation system of Belousov-Zhabotinskii type with aldehyde as substrate is described for the first time. Oscillations of the concentration of Mn(III) ions can be followed spectrophotometrically or potentiometrically with a Pt electrode in a relatively narrow concentration range of the substrate. In contrast to the analogous reaction with malonic acid, no oscillations of the concentration of Br- ions were detected by a bromide ion selective electrode. This together with the fact that the concentration of Mn(III) ions oscillates even at relatively high bromine concentrations suggests that oscillations of the concentration of the redox catalyst Mn(II)/Mn(III) are probably controlled by organic radicals rather than by Br- ions.

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Belousov–Zhabotinskii type oscillation reaction with glycerol and kinetics of reactions between the system components

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19872375 ◽

1987 ◽

Vol 52 (10) ◽

pp. 2375-2382 ◽

Cited By ~ 5

Author(s):

Ľubica Adamčíková ◽

Peter Ševčík

Keyword(s):

Oscillation System ◽

Chemical Oscillations ◽

Oscillation Reaction ◽

Reaction Solution ◽

System Components ◽

Probable Source ◽

Belousov Zhabotinskii Reaction ◽

Kinetics Of ◽

Hydrolysis Of ◽

Type Oscillation

Glycerol causes chemical oscillations in Belousov-Zhabotinskii reaction in a closed system as well as in a reaction solution bubbled with nitrogen. Since the oxidation of glycerol with bromate ions does not proceed autocatalytically and bromine in the oxidation state 0 or +1 in the absence of light does not react with glycerol, hydrolysis of bromine is the probable source of bromide ions in the studied oscillation system.

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Redox Potential - (Electronic) Structure Relationships in 18- and 17-Electron Mononitrile (or Monocarbonyl) Diphosphine Complexes of Re and Fe

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20010139 ◽

2001 ◽

Vol 66 (1) ◽

pp. 139-154 ◽

Cited By ~ 11

Author(s):

M. Fátima C. Guedes Da Silva ◽

Luísa M. D. R. S. Martins ◽

João J. R. Fraústo Da Silva ◽

Armando J. L. Pombeiro

Keyword(s):

Cyclic Voltammetry ◽

Electronic Structure ◽

Binding Sites ◽

Closed Shell ◽

Carbonyl Complexes ◽

Metal Centre ◽

Pt Electrode ◽

Metal Site ◽

Oxidation Potentials ◽

First Time

The organonitrile or carbonyl complexes cis-[ReCl(RCN)(dppe)2] (1) (R = 4-Et2NC6H4 (1a), 4-MeOC6H4 (1b), 4-MeC6H4 (1c), C6H5 (1d), 4-FC6H4 (1e), 4-ClC6H4 (1f), 4-O2NC6H4 (1g), 4-ClC6H4CH2 (1h), t-Bu (1i); dppe = Ph2PCH2CH2PPh2), or cis-[ReCl(CO)(dppe)2] (2), as well as trans-[FeBr(RCN)(depe)2]BF4 (3) (R = 4-MeOC6H4 (3a), 4-MeC6H4 (3b), C6H5 (3c), 4-FC6H4 (3d), 4-O2NC6H4 (3e), Me (3f), Et (3g), 4-MeOC6H4CH2 (3h); depe = Et2PCH2CH2PEt2), novel trans-[FeBr(CO)(depe)2]BF4 (4) and trans-[FeBr2(depe)2] (5) undergo, as revealed by cyclic voltammetry at a Pt-electrode and in aprotic non-aqueous medium, two consecutive reversible or partly reversible one-electron oxidations assigned as ReI → ReII → ReIII or FeII → FeIII → FeIV. The corresponding values of the oxidation potentials IE1/2ox and IIE1/2ox (waves I and II, respectively) correlate with the Pickett's and Lever's electrochemical ligand and metal site parameters. This allows to estimate these parameters for the various nitrile ligands, depe and binding sites (for the first time for a FeIII/IV couple). The electrochemical ligand parameter show dependence on the "electron-richness" of the metal centre. The values of IE1/2ox for the ReI complexes provide some supporting for a curved overall relationship with the sum of Lever's electrochemical ligand parameter. The Pickett parametrization for closed-shell complexes is extended now also to 17-electron complexes, i.e. with the 15-electron ReII and FeIII centres in cis-{[ReCl(dppe)2]}+ and trans-{FeBr(depe)2}2+, respectively.

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Analysis of Bromide Ion in Wine by Ion Selective Electrode

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/59.1.53 ◽

1976 ◽

Vol 59 (1) ◽

pp. 53-55

Author(s):

James E Graf ◽

Troy E Vaughn ◽

William H Kipp

Keyword(s):

Country Of Origin ◽

Ion Selective Electrode ◽

Ion Concentration ◽

Selective Electrode ◽

Bromide Ion

Abstract The use of the bromide ion selective electrode for the determination of bromide ion in wine has been found to be rapid and reliable. The method has been used for still wines and carbonated wines and is applicable to all wines regardless of their country of origin. The method consists of treating a 50 ml aliquot of wine with 2 ml each of 3.75M H3PO4, saturated KNO3, and 1M CuSO4. After 10 min the electrodes are immersed in the samples and a millivolt reading is obtained. One hundred μl 500 ppm bromide ion standard is added and the millivolt reading is taken. Bromide ion concentration in the wine = (CΔ × 1)/((antilog ΔE/S) − 1) where CΔ = 1, ΔE = the change in potential expressed in millivolts, and S = the electrode slope.

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Kinetics of oxidation of α-ketoglutaric acid with Ce(IV) ions in relation to Belousov-Zhabotinskii reaction

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822831 ◽

1982 ◽

Vol 47 (11) ◽

pp. 2831-2837 ◽

Cited By ~ 4

Author(s):

Ľudovít Treindl ◽

Vasil Dorovský

Keyword(s):

Redox Reaction ◽

Platinum Electrode ◽

Activation Parameters ◽

Enol Form ◽

Kinetics Of Oxidation ◽

First Order ◽

Redox Catalyst ◽

Oscillation Reaction ◽

Belousov Zhabotinskii Reaction ◽

Kinetics Of

Oxidation of α-ketoglutaric acid with Ce(IV) ions in a solution of sulphuric acid is a reaction of the first order with respect to both Ce(IV) ions and substrate, is acid catalysed, and its rate is proportional to the reciprocal square of the equilibrium HSO4- concentration. From the temperature dependence of the rate constant in 1.5M-H2SO4, the activation parameters were determined as ΔH##f = 57 kJ/mol and ΔS##f = -45 J mol-1 K-1. The redox reaction proper consists apparently of two steps: in the first one, the enol form of α-ketoglutaric acid reacts with Ce(IV) ions with the formation of the corresponding radical; in the second one, the latter is oxidized further with Ce(IV) to give malonic and succinic acids. Conditions are indicated under which α-ketoglutaric acid serves as substrate for the Belousov-Zhabotinskii oscillation reaction in the presence of Ce(IV)-Ce(III) redox catalyst. Oscillations of Ce(IV) and Br2 concentrations, shifted in phase, can be recorded polarographically with a rotating platinum electrode.

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Oscillation system of Belousov-Zhabotinskii type in presence of Cl- ions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862693 ◽

1986 ◽

Vol 51 (12) ◽

pp. 2693-2701 ◽

Cited By ~ 4

Author(s):

Marta Mrákavová ◽

Ľudovít Treindl

Keyword(s):

Reaction Mechanism ◽

Ethyl Ester ◽

Reaction System ◽

Oscillation System ◽

Low Concentration ◽

Redox Catalyst ◽

Probable Reaction Mechanism ◽

Oxobutanoic Acid ◽

Probable Reaction

A modified Belousov-Zhabotinskii oscillation system involving ethyl ester of 3-oxobutanoic acid and Fe(phen)32+ - Fe(phen)33+ as redox catalyst is remarkable in that it shows an oxygen-induced excitability. The oscillating state, involving 4-5 oscillations in the absorbancy of Fe(phen)32+ ions, comes soon to its end but can be restored by shaking the reaction system, thus incresing the transport of oxygen from the air. This phenomenon is not influenced by Cl- ions in a low concentration, but if this is equal to 10-3 mol dm-3 or higher, no oscillations are observed, the increase of the concentration of Fe(phen)32+ ions is autocatalytic in character and can be reproduced several times by shaking or stirring the solution. These phenomena are discussed in terms of a probable reaction mechanism.

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Solid-contact Ca2+-selective electrodes based on two-dimensional black phosphorus as ion-to-electron transducers

RSC Advances ◽

10.1039/c7ra07743b ◽

2017 ◽

Vol 7 (69) ◽

pp. 43905-43908 ◽

Cited By ~ 5

Author(s):

Lijuan Kou ◽

Minglang Fu ◽

Rongning Liang

Keyword(s):

Black Phosphorus ◽

Two Dimensional ◽

Solid Contact ◽

Selective Electrode ◽

First Time

A solid-contact Ca2+-selective electrode with two-dimensional black phosphorus as the solid contact was developed for the first time.

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BGO/AlFu MOF core shell nano-composite based bromide ion-selective electrode

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2020.104375 ◽

2020 ◽

Vol 8 (5) ◽

pp. 104375 ◽

Cited By ~ 1

Author(s):

Navjot Kaur ◽

Jagseer Kaur ◽

Rahul Badru ◽

Sandeep Kaushal ◽

Prit Pal Singh

Keyword(s):

Ion Selective Electrode ◽

Core Shell ◽

Selective Electrode ◽

Nano Composite ◽

Bromide Ion

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Mechanism of bromide ion oxidation on Pt electrode in CH2Cl2

Journal of Electroanalytical Chemistry ◽

10.1016/s0022-0728(81)80428-7 ◽

1981 ◽

Vol 126 (1-3) ◽

pp. 189-198 ◽

Cited By ~ 11

Author(s):

Marina Mastragostino ◽

Sergio Valcher ◽

Paola Lazzari

Keyword(s):

Pt Electrode ◽

Bromide Ion

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Rapid and Automated Analytical Methods for Redox Species Based on Potentiometric Flow Injection Analysis Using Potential Buffers

Journal of Automated Methods and Management in Chemistry ◽

10.1155/2011/516165 ◽

2011 ◽

Vol 2011 ◽

pp. 1-14 ◽

Cited By ~ 2

Author(s):

Hiroki Ohura ◽

Toshihiko Imato

Keyword(s):

Flow Injection ◽

Analytical Methods ◽

Injection Technique ◽

Selective Electrode ◽

Redox Species ◽

Injection Method ◽

Highly Sensitive ◽

Bromide Ion ◽

Oxidative Species

Two analytical methods, which prove the utility of a potentiometric flow injection technique for determining various redox species, based on the use of some redox potential buffers, are reviewed. The first is a potentiometric flow injection method in which a redox couple such as Fe(III)-Fe(II), Fe-Fe(CN), and bromide-bromine and a redox electrode or a combined platinum-bromide ion selective electrode are used. The analytical principle and advantages of the method are discussed, and several examples of its application are reported. Another example is a highly sensitive potentiometric flow injection method, in which a large transient potential change due to bromine or chlorine as an intermediate, generated during the reaction of the oxidative species with an Fe(III)-Fe(II) potential buffer containing bromide or chloride, is utilized. The analytical principle and details of the proposed method are described, and examples of several applications are described. The determination of trace amounts of hydrazine, based on the detection of a transient change in potential caused by the reaction with a Ce(IV)-Ce(III) potential buffer, is also described.

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