Decomposition reactions catalyzed by a solid additive

Studies of the influence of additives on rates of salt decompositions are often directed towards the formulation or confirmation of a mechanism 

Jacobs and Whitehead [59] conclude that no single mechanistic explanation accounts for the effects of various catalysts in accelerating the decomposition rate of NH4C104. They identify three distinct modes of action (see also Chap. 4, Sect. 4.1). 

In none of these examples is there any evidence that the catalytic behaviour results from direct chemical interaction between the solid reactant and the solid additive. 

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