Arrhenius plot oxygen isotopes

Figure 2. Arrhenius plots for the heterogeneous exchange of isotopic oxygen on NgO and Au/MgO catalysts of varying gold dispersion. See Table I for catalyst code numbers.

Figure 10. Arrhenius plots of oxygen isotope rate constants for select feldspar-salt solution (a) and clay/mica-fluid systems based on the simplified pseudo-first order surface area rate model (Eqn. 96).

The first term to the right of Eq. 15 is the apparent activation energy determined from the Arrhenius plot (48 kcal.mol ). The second term depends upon the variation of surface oxygen coverage with temperature. The latter was determined to be zero from a pressure dependence study of the isotope exchange rate. In the pressure dependance study, the total oxygen partial pressure was reduced to 20% and 2% of one atmosphere, respectively. The molar ratio of 02 to 2 was maintained at 1 1. At conversions less than 10%, the rate of production in each case was identical to that shown in Fig. 4. This clearly shows... 

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