Arrhenius plots for reactions

They observed abrupt changes in the slope of Arrhenius plots for reactions catalyzed by NADH oxidase and p-lactate oxidase that correlate well with phase transitions detected by the ESR spectra of the nitroxide spin labels bound covalently to the enzymes (Table 5.4). 

Fig. 3. Arrhenius plot for reaction (5a). O From photochemical experiments23 A based on thermal reaction data.

Fio. 18. Arrhenius plot for reaction of spectroscopic carbon rods with carbon dioxide at 1 atm. pressure. 

Fig. 26. Arrhenius plots for reaction of raw and heat-treated rods of Ceylon graphite with carbon dioxide at 1 atm. pressure. [After F. Rusinko, Jr., Ph.D. Thesis, The Pennsylvania State University, 1968.1...

Figure 12.1. Arrhenius plot for reaction with negative apparent activation energy (schematic).

Figure 12.2. Arrhenius plots for reactions with shift in rate control but no change in form of rate equation (schematic). Left shift to different step within same pathway right shift to alternative, parallel pathway. Dashed lines are linear extrapolations into respective other temperature regions (from Helfferich and Savage [14]).

P igure 43 shows an Arrhenius plot for reaction (xv), and leads to... 

If it had been decided to plot log(/tR/dm3 moh s- ) versus reciprocal temperature in order to obtain an Arrhenius plot for Reaction 6.1, what would have been the value of the slope of the straight line in this case ... 

Figure 2. Variations in E obtained Figure 3. Arrhenius plot for reaction from the early data [ 16] complicated by diffrjsion...

Fig. 8. Deviations between and k rrheniun (the values of k extrapolated to low temperatures from linear Arrhenius plots), for reactions of the anion of 2,4,6-trinitrotoluene with various acids 0,HF V, CHsCHOOH A, CH2CICOOH. (From Ref. 23 copyright 1969 by the American Chemical Society reproduced by permission of the copyright owner.)...

Figure 3. Arrhenius plots for reaction rate constants...

Fig. 8. Arrhenius plots for the formic acid decomposition on palladium foil (1) and small pieces of this foil (2) at a higher temperature range, when hydrogen evolving as a product of the reaction was absorbed by Pd and transformed into the /3-Pd-H hydride phase. At the lower temperature range the reaction proceeds on the a-Pd-H phase, with a higher activation energy when the foil was hydrogen pretreated (2a), and a lower activation energy for a degassed Pd foil (3a). After Brill and Watson (57).

The recombination reaction proceeding on nickel-copper alloy films rich in copper and on copper itself maintained a constant value of the activation energy of about 1 kcal/mole. The Arrhenius plot for an alloy film Ni20Cu80 is represented in Fig. 14. 

Figure 5.1 shows an Arrhenius plot for the reaction O -b N2 NO -b N the plot is linear over an experimental temperature range of 1500 K. Note that the rate constant is expressed per molecule rather than per mole. This method for expressing k is favored by some chemical kineticists. It differs by a factor of Avogadro s number from the more usual k. 

Figure 4. Arrhenius plots for the formation of formaldehyde or acetaldehyde from methanol or ethanol, normalized by the number of vanadiums (open symbols) and by the amount of oxygen uptake measured at the temperature of reaction (filled symbols).

Figure 8. Rate of carbon monoxide oxidation on calcined Pt cube monolayer as a function of temperature [27]. The square root of the SFG intensity as a function of time was fit with a first-order decay function to determine the rate of CO oxidation. Inset is an Arrhenius plot for the determination of the apparent activation energy by both SFG and gas chromatography. Reaction conditions were preadsorbed and 76 Torr O2 (flowing). (Reprinted from Ref. [27], 2006, with permission from American Chemical Society.)...

Figure 5.4-12. Arrhenius plot for a catalytic heterogeneous reaction. 

Figure 5.4-36. Fit of first-order kinetics for three Figure 5.4-37. Arrhenius plot for rate constants isothermal reaction periods (reprinted with obtained from the isothermal reaction periods permission from Landau et al. (1994). Copyright (reprinted with permission from Landau et al. (1994) American Chemical Society). (1994). Copyright (1994) American Chemical...

Nonlinear Arrhenius Plots For most organic reactions, plots of In k versus l/T are linear, and afford and A values in accord with the Arrhenius equation." However, for systems where QMT is involved, rate constants fall off less steeply than expected as temperatures are lowered, which often leads to upwardly curved Arrhenius plots as illustrated in Figure 10.2 ... 

As a model esterification reaction, the formation of ethyl lactate has been studied and its complete kinetic and thermodynamic analysis has been performed. The formation rate of ethyl lactate has been examined as a function of temperature and catalyst loading. In early experiments, it was determined that lactic acid itself catalyzes esterification, so that there is significant conversion even without ion exchange resin present. The Arrhenius plot for both resin-catalyzed and uncatalyzed reactions indicates that the uncatalyzed... 

All reactions at 19 °C, 0 °C, and -19 °C were of the first order internally, up to at least 90% conversion, and all went to completion. Details are given in Tables 1-3. The first-order rate constant, kt, is directly proportional to the acid concentration as shown by the constancy of the values of kp = 1/[HClO4]0. The Arrhenius plot for kp gave... 

Figure 15.2 The Eyring (circles) and the Arrhenius (squares) plot for reaction 15.5.

In contrast to propane hydrogenolysis, the Arrhenius plots for cyclopropane hydrogenolysis on both surfaces exhibit no deviations from linearity over the entire temperature range studied, and the reaction orders in both hydrogen and cyclopropane are essentially zero". These results have... 

---