Arrhenius equation


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Ar·rhe·ni·us e·qua·tion

(ă-rē'nē-ŭs),
an equation relating chemical reaction rate (k) to the absolute temperature (T) by the equation: d(ln k)/dT) = ΔEa/RT2 where Ea is the activation energy and R is the universal gas constant.
[Svante Arrhenius]
Farlex Partner Medical Dictionary © Farlex 2012

Arrhenius equation

(ă-rā′nē-us)
[Svante Arrhenius, Swedish chemist and Nobel laureate, 1859–1927]
A mathematical formula that specifies the influence of temperature on the rate of a chemical reaction. In general, a higher temperature produces a faster reaction. The equation is used in industry and pharmacy to predict shelf life of reagents and pharmaceuticals.
Medical Dictionary, © 2009 Farlex and Partners

Arrhenius,

Svante, Swedish chemist and Nobel laureate, 1859-1927.
Arrhenius doctrine - the theory of electrolytic dissociation that became the basis of modern understanding of electrolytes. Synonym(s): Arrhenius law
Arrhenius equation - an equation relating chemical reaction rate to the absolute temperature.
Arrhenius law - Synonym(s): Arrhenius doctrine
Arrhenius-Madsen theory - that the reaction of an antigen with its antibody is a reversible reaction.
Medical Eponyms © Farlex 2012
References in periodicals archive ?
The dependence on temperature was expressed by the shift factor [a.sub.T] through the Arrhenius equation. For all compounds, a viscosity law at 70[degrees]C was obtained, whose dependence on filler content was expressed by the factor [a.sub.[phi]] through the Krieger-Dougherty law.
The temperature dependence based on the Arrhenius equation (Eq.
As stated above, life estimation testing as used by CET is based on the Arrhenius equation which describes a first order reaction, such as a chemical reaction.
Once the activation energy is known, equivalent cure times for a time-temperature profile can be accurately calculated using the Arrhenius equation 9.
sup.-1]) sup.-1]) sup.-1]) 4a 3.43 50.5 164 279 4b 3.19 45.9 171 239 4c 3.01 45.1 116 210 The activation energy for [gamma] and [beta] relaxation processes was calculated by applying the Arrhenius equation:
An alternative approach is to assume that the temperature dependence can be represented by an Arrhenius equation from which an activation energy can be calculated, t = A exp (E/RT) where A is a constant, E is the activation energy, R is the gas constant, and T is the cure temperature in degrees kelvin.
where [gamma] is the rate of strain tensor, [eta] is the viscosity of the polymer melt, which may be written with the modified Cross model and the Arrhenius equation, respectively, as below
It is fairly accepted that this superposition manifests itself from the molecular behavior and therefore, equations based on the activation energy (E), such as the Arrhenius equation have been proposed.
Using this plastometer, the yield stress of EMC was directly measured at the actual molding temperature and its temperature dependency was clarified and characterized using the Arrhenius equation. And also, the low shear viscosities below 10 [s.sup.-1] were obtained.
Although Arrhenius equation could have been used in construction of the master curves, WLF equation have been taken in the present study.