Delayed primary intention

There are, however, other phenomena that can lead to a delay of a chain reaction. In autoxida-tion of hydrocarbons, for example, the primary reaction product is a peroxide that, in turn, can act as initiator (see Example 9.3 in Section 9.6.2). Unless an initiator has intentionally been added, the reaction may start at a very low rate and then pick up speed as it produces its own initiator. Such behavior is best classified as autocatalytic (see Section 8.9). 

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