energy of activation


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en·er·gy of ac·ti·va·tion (Ea),

energy that must be added to that already possessed by a molecule or molecules in order to initiate a reaction; usually expressed in the Arrhenius equation relating a rate constant to absolute temperature.
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The free energy of activation means the energy required by a thermodynamic process to take place [22].
The energy of activation 6Ev , was evaluated from the Arrhenius relation [21, 22] and the representativeconcentration shown in Figure 4 in AN of 0.01 mol.dm-3LiBr while Figures 5 and 6 in 3-HPN and50% AN +3- HPN mixture of 0.01 mol.dm-3 NaBr respectively.where y is viscosity R is the universal gas constant.
It is obvious from the calculated value of the energy of activation obtained from the slope of the plot (Figure 3) of the Arrhenius equation:
The energy required is called the energy of activation.
The excess Gibbs free energy of activation of viscous flow was calculated from equation (3) and recorded in Table-4.
Assuming an Arrhenius-like temperature dependency k(T) = A exp(-[E.sub.a]/(RT)), the energy of activation Ea and the pre-exponential factor A are obtained by linear regression of -lnk versus 1/T.
1/[degrees]K, one can calculate the compound's specific energy of activation ([E.sub.A]) through what is called an Arrhenius plot (refs.
where [a.sub.T] is the horizontal shift factor, [E.sub.H] is the horizontal flow energy of activation, R is the gas universal constant, T is the temperature, [T.sub.ref] is the reference temperature.
The energy of activation of cure was deduced using Arrehenius kinetics.
The Gibb's free energy of activation has positive value showing the stable quadridentate nature of ligand surrounding the metal center.