The √t law in solid‐phase reactions. Analysis of the hypothesis on rate constant distribution

Abstract

The reaction C2Hs + 0 2 -C2Hs02 in glassy methanol-d4 and the H-atom abstraction by CH:%, C~H S , and n-C4Hy radicals in C~H S O H + C2DsOH and CDBCH~OH + C~D S O H glassy mixtures have been studied by electron spin resonance. The analysis of the dependence of the reaction rates on the concentration of 0 2 (oxidation) and CzHsOH, CD&HzOH (H-atom abstraction) has shown that the fi law is not conditioned by the existence of regions characterized by different rate constants.

Detection of deep traps for gas molecules in methanol/water glasses at 77 K

“…The kinetics in the solid phase is sometimes described by a time-dependent rate constant. Under our experimental conditions, the applicability of this description may be verified by the coincidence of the kinetic curves for various oxygen concentrations plotted in the coordinates [8,13] …”

“…It has been verified, as in Ref. [8], that the decay of ethyl radicals in our system is determined by the process C2Hs + O2…”

“…The oxygen solubility in methanol with 9% of D20 was (4 + 0.8)• Is cm'3atm -1 [8]. Changes in the solubility with varying amount of water were neglected.…”

“…The technique of ethyl radical generation, as well as procedures for measurement of their concentration and saturation of the samples with gas are described in Ref. [8].…”

“…The concentrations of nitrogen and oxygen in the samples were determined using the solubility of these gases at room temperature [8]. The oxygen solubility in methanol with 9% of D20 was (4 + 0.8)• Is cm'3atm -1 [8].…”