Arrhenius equation


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Arrhenius equation

[ar′rā·nē·əs i′kwā·zhən]
(physical chemistry)
The relationship that the specific reaction rate constant k equals the frequency factor constant s times exp (-Δ Hact/ RT), where Δ Hactis the heat of activation, R the gas constant, and T the absolute temperature.
References in periodicals archive ?
Kinetics analysis indicated that NO reduction over reduced LNT catalyst followed the Arrhenius equation with the first order dependence on NO inlet concentration and the apparent activation energy of 180[+ or -]14 kJ/mol, regardless of the thermal aging or the type of reductant.
In order to simulate the effect of high mechanical shear stress in the ultrahigh speed TSE at high speed and have a qualitative analysis on the difference between thermal and mechanical effects on the depolymerization of the PS, we used the prefactor and activation energy values determined for the Brabender batch mixer experiment (with only thermal effects) in the Arrhenius equation with the depropagation rate constants for the reactions occurring at different screw speeds in TSE.
From the intercept of the straight line described by the Arrhenius equation, [D.sub.0] is calculated as 2.05 x [10.sup.-5] [m.sup.2] [s.sup.-1].
This plot shows a linear relationship between the Log R and 1/T, indicating a good fit for the Arrhenius equation. From Figure 6, the activation energy values were calculated as 48.37 KJ/mole (0.50 eV), 62.88 KJ/mole (0.65 eV), and 76.96 KJ/mole (0.79 eV) for 0, 2, and 4 wt% of MWCNTs in PVP nanocomposite fibers, respectively.
Similar dependence of plots of Log [sigma] (conductivity) and Log R (resistance) versus 1/T ([K.sup.-1]) clearly indicated that the thermal process were adaptable the Arrhenius equation (Fig.
The reaction was found to be accurately of the first order at the high pressures and the observed rate coefficient is expressed by the following Arrhenius equation: ktotal uninhibited = 107.98 0.6 (s 1) exp167 7.8 (kJ/mole)/RT The activation energy was calculated at 1677.98kJ/mol and identified with the dissociation of C-Cl bond.
These tests should be run at various temperatures so that the Arrhenius equation can be applied.
k [[s.sup.-1]] is the reaction rate constant expressed by the Arrhenius equation (2) where A [[s.sup.-1]], E [J.[mol.sup.-1]] and R [J.[mol.sup.-1].[K.sup.-1]] are pre-exponential factor, activation energy and gas constant respectively.
For this aim, the member lnA in the Arrhenius equation
The [k.sub.M] values increase with the increase in dehydration temperature in accordance with the Arrhenius equation. Therefore, the kinetic parameters of the PAM hydrogel dehydration ([E.sub.a] = 52.2 kJ[mol.sup.-1]; ln (A/[min.sup.-1]) = 17.8) were calculated using the Arrhenius equation.
Moreover, for estimation of the activation energy of rehydration, the data obtained from the Peleg's Model were fitted to the Arrhenius equation, and the activation energy was calculated as 38.14 kJ/mol.