Calculation of activation energy of electron-transfer reaction between MnO4 ? and MnO 4 2? ions in aqueous medium

1977 ◽  
Vol 26 (2) ◽  
pp. 422-423
Author(s):  
E. D. German
Keyword(s):  
Activation Energy ◽  
Electron Transfer ◽  
Aqueous Medium ◽  
Transfer Reaction ◽  
Electron Transfer Reaction

scholarly journals Nonenzymatic NADH-Dependent Reduction of Keggin-Type 12-Tungstocobaltate(III) in Aqueous Medium

2011 ◽  
Vol 8 (3) ◽  
pp. 1152-1157
Author(s):  
Prabla Kumari ◽  
Alaka Das ◽  
Dillip Kumar Baral ◽  
A. K. Pattanaik ◽  
P. Mohanty
Keyword(s):  
Electron Transfer ◽  
Transition State ◽  
Aqueous Medium ◽  
Transfer Reaction ◽  
Activation Parameters ◽  
Electron Transfer Reaction ◽  
Transfer Reactions ◽  
Electron Transfer Reactions ◽  
First Order ◽  
Kinetics Of

The kinetics of the electron transfer reaction of NADH with 12-tungstocobaltate(III) has been studied over the range 5.07 ≤ 104[NADH] ≤ 15.22 mol dm-3, 7.0 ≤ pH ≤ 8.0 and 20 ≤ t ≤ 35oC in aqueous medium. The electron transfer reaction showed first-order dependence each in [NADH]Tand [12-tungstocobaltate(III)]T. The products of the reaction were found to be NAD+and 12-tungstocobaltate(II). The activation parameters ΔH#(kJ mol-1) and ΔS#(JK-1mol-1) of the electron transfer reactions were found to be 64.4±1.8 and -48.86±6.0. Negative value of ΔS#is an indicative of an ordered transition state for the electron transfer reaction.

scholarly journals The Kinetics of Electron Transfer Reaction of Methylene Blue and Titanium Trichloride in different Solvents

2017 ◽  
Vol 6 (2) ◽  
pp. 940-957 ◽  
Author(s):  
Rehana Saeed Saeed
Keyword(s):  
Activation Energy ◽  
Methylene Blue ◽  
Electron Transfer ◽  
Transfer Reaction ◽  
Reaction Pathway ◽  
Reaction Medium ◽  
Electron Transfer Reaction ◽  
Rate Of Reaction ◽  
Titanium Trichloride ◽  
Kinetics Of

The kinetics of the electron transfer reaction of methylene blue and titanium trichloride was studied in water and aqueousalcoholic solvents at various temperatures by spectrophotometry. The rate of reaction was observed by taking change inabsorbance as a function of time at λmax 660 nm. The reaction is pseudo-first order, dependent on concentration of titaniumtrichloride at fixed concentration of methylene blue.The effect of solvent was studied in the pH/Ho range from 4 to 7. It was observed that the rate of reaction increased withincrease in polarity of the reaction medium. The rate of reaction was high in acidic condition and decreased with furtherincrease in hydrogen ions activity. The increase in temperature increased the rate of electron transfer reaction of methyleneblue and titanium trichloride. Activation energy (Ea) was calculated by Arrhenius relation. The absence of any reactionintermediate was confirmed by spectroscopic and kinetic investigations. A plausible mechanism for the reaction in line withouter-sphere reaction pathway has been proposed. Thermodynamic parameters such as activation energy (Ea), enthalpychange (∆H), free energy change (∆G) and entropy change (∆S) were also evaluated.

scholarly journals Non enzymatic NADH-dependent reduction of Cis-[Co(en)2(H2O)2]3+ in aqueous medium

2018 ◽  
Vol 6 (2) ◽  
pp. 163
Author(s):  
Bharati Behera ◽  
Jashoda Behera
Keyword(s):  
Electron Transfer ◽  
Aqueous Medium ◽  
Transfer Reaction ◽  
Activation Parameters ◽  
Electron Transfer Reaction ◽  
Transfer Reactions ◽  
Electron Transfer Reactions ◽  
First Order ◽  
Order Dependence ◽  
Kinetics Of

The kinetics of the electron transfer reaction of NADH with Cis-[Co(en)2(H2O)2]3+ has been studied over the range 1.0 ≤ 102 [NADH] ≤ 3.0 mol dm-3, 7.0 ≤ pH ≤ 8.0 and 200C ≤ t ≤ 350C in aqueous medium. The rate of electron transfer reaction was found to be first-order dependence each in [NADH]T and Cis-[Co(en)2(H2O)2]3+T. The products of the reaction were found to be NAD+ and Co(II). The corresponding activation parameters of the electron transfer reactions were found to be as ΔH#=27.55 kJ mol-1 and  ΔS#= -189.35 JK-1mol-1. 

scholarly journals Electron transfer studies of a conventional redox probe in human sweat and saliva bio-mimicking conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. Krishnaveni ◽  
V. Ganesh
Keyword(s):  
Electron Transfer ◽  
Crystalline Phase ◽  
Liquid Crystalline ◽  
Transfer Reaction ◽  
Electron Transfer Reaction ◽  
Redox Couple ◽  
Liquid Crystalline Phase ◽  
Transfer Reactions ◽  
Redox Probe ◽  
Human Sweat

AbstractModern day hospital treatments aim at developing electrochemical biosensors for early diagnosis of diseases using unconventional human bio-fluids like sweat and saliva by monitoring the electron transfer reactions of target analytes. Such kinds of health care diagnostics primarily avoid the usage of human blood and urine samples. In this context, here we have investigated the electron transfer reaction of a well-known and commonly used redox probe namely, potassium ferro/ferri cyanide by employing artificially simulated bio-mimics of human sweat and saliva as unconventional electrolytes. Typically, electron transfer characteristics of the redox couple, [Fe(CN)6]3−/4− are investigated using electrochemical techniques like cyclic voltammetry and electrochemical impedance spectroscopy. Many different kinetic parameters are determined and compared with the conventional system. In addition, such electron transfer reactions have also been studied using a lyotropic liquid crystalline phase comprising of Triton X-100 and water in which the aqueous phase is replaced with either human sweat or saliva bio-mimics. From these studies, we find out the electron transfer reaction of [Fe(CN)6]3−/4− redox couple is completely diffusion controlled on both Au and Pt disc shaped electrodes in presence of sweat and saliva bio-mimic solutions. Moreover, the reaction is partially blocked by the presence of lyotropic liquid crystalline phase consisting of sweat and saliva bio-mimics indicating the predominant charge transfer controlled process for the redox probe. However, the rate constant values associated with the electron transfer reaction are drastically reduced in presence of liquid crystalline phase. These studies are essentially carried out to assess the effect of sweat and saliva on the electrochemistry of Fe2+/3+ redox couple.

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