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Activation energy graphical method

An alternative method graphically determines the slope in an Arrhenius plot The natural logarithm of the heat release rate is plotted as a function of the reciprocal temperature (in K). Hence, it can be verified that the points obtained are on a straight line, meaning that they follow Arrhenius law and the slope corresponds to the ratio E/R that delivers the activation energy. In Figure 11.5, the abscissa is... [Pg.289]

Horjales and Branden (1985) constructed a diamond lattice model by docking cyclohexanol and its monoethyl derivatives into the experimentally determined active site of the enzyme (X-ray crystallographic structure, 1982), using computer graphics and energy minimization methods. The lattice positions were classified as allowed, forbidden or boundary depending their distances to protein atoms (Figure 8). The... [Pg.488]

Systems that are governed by reaction kinetics show well-defined behaviors as a function of temperature and potential. If the system can be described as being controlled by a single activation-energy-controlled process, graphical methods can be used to cause the data to superpose. [Pg.357]

Figure 16-14 A graphical method for determining activation energy, E. At each of several different temperatures, the rate constant, k, is determined by methods such as those in Sections 16-3 and 16-4. A plot of In k versus 1/T gives a straight line with negative slope. The slope of this straight line is —EJR. Use of this graphical method is often desirable, because it partially compensates for experimental errors in individual k and T values. Figure 16-14 A graphical method for determining activation energy, E. At each of several different temperatures, the rate constant, k, is determined by methods such as those in Sections 16-3 and 16-4. A plot of In k versus 1/T gives a straight line with negative slope. The slope of this straight line is —EJR. Use of this graphical method is often desirable, because it partially compensates for experimental errors in individual k and T values.
The following example demonstrates a graphical method for determining the activation energy of a reaction. [Pg.530]

There are other methods that predict reactivity more reliably than the oxygen balance method. These methods, however, require the use of data generated by measurements. Stull devised a relatively simple Reaction Hazard Index or RHI that used both kinetic and thermodynamic data measurements. This index is a graphic model (nomagraph) that uses the Arrhenius activation energy and the decomposition temperature The latter term is the maximum adiabatic temperature reached by the products of a decomposition reaction. If data are available or can be measured, the RHI may be a very useful method to predict reactivity. Coffee described a method that predicts the explosive potential of a compound using thermal stability (measured), impact sensitivity (measured), and the heat of reaction (calculated). Compounds found to be thermally unstable and sensitive to impact were explosive. [Pg.291]

Activation energy calculated by graphical method using formula Ej ... [Pg.154]

Systematic studies of reaction energies for the abstraction of H2 from MH4 (equation 5) for M = Si, Ge, Sn and Pb were reported by Dyall who also compared the results of the DHF calculations with those of other methods (ECP, PT)126, by Schwerdtfeger and coworkers48b who included also the eka-lead element 114 and by Thiel and coworkers105 who studied also the activation barriers for this reaction. More recent computations concentrated on the evaluation of the quality of the various theoretical approaches103106. The results of the calculations are collected in Table 4 and are shown graphically in Figure 3a. [Pg.17]


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See also in sourсe #XX -- [ Pg.357 , Pg.358 , Pg.359 ]




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