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Show Unfortunately, it can only be solved in the context of the kind of full scale simulations discussed earlier. However, in the case where there is only one mode of destruction simplifications are possible and leads to a direct relationship between the number of nines destruction and the rate constants. Consider the situation where we are concerned with the relative incinerability of two substances Hz and Hz', then if the mechanism for destruction is unique for these two compounds, we can write - d(Hz)/dt = k (R) (Hz) and -d(Hz')/dt = k'(R) (Hz') where k and k' are the rate constants for radical R attack on Hz and Hz'. Dividing the two equations into each other and integrating, we find In[(Hz)i/(Hz)f]/ln[(Hz')/(Hz')f] = k/k' The term on the left is precisely the ratio of the number of nines destruction. Thus we can see that the ratio of incinerability is related to the ratio of rate constants. Rate constants can usually be expressed in the form k = A x Exp (-E/RT) where E is the activation energy, A is a constant, R is the gas constant and T the temperature. They can thus vary a great deal. This means that for large degrees of incinerability there should be correspondingly large differences in incinerability between different substances. The reader is reminded that this relation holds only if there is one single mechanism for destruction. This is rarely the case. Discrepancies can be expected. However in some cases the discrepancies are so large that it is possible to reject possible mechanisms. This will be utilized in a subsequent section. KINETIC INFORMATION ON CHLOROBENZENES In the following we describe the existing information on the thermal 6 |