Page 99 - Elements of Chemical Reaction Engineering 3rd Edition

Sec. 3.1 Basic Definitions 71
Solution
By converting Equation (3-3) to log base 10,
(
log k = log A - 2.3~ F) (E3-1.1)
E
1

we can use semilog paper to determine E quite readily by first forming the follow-
ing table from the data above:

k (SI) 0.00043 0.00103 0.00180 0.00355 0.00717
O I - -1000/T (K-I) 3.05 3.0

Then we plot the data directly on semilog paper as shown in Figure E3- 1.1.

Finding the
activation energy.
Plot (In k) vs. (l/T)

x IOS(K”l
Figure E3-1.1

Although the slope can be determined by a number of methods as described
in Appendix D, the decade method is chosen here. For two different points on
Fi,gure E3-1.1, we have

Subtracting yields