Flame Cooling of Halogens

Active radicals are captured by halogen X in the following maimer  

Important for flammability is the chain branching reaction mechanism. Chain branching effects a rapid increase of the active radicals. 

For this reason the rate of combustion is strongly increased, which may reach the character of an explosion. Flame cooling traps the radicals, which are notorious for accelerating the reaction rate. 

Antimony trioxide interferes with the combustion reaction as 

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