chain carrier

In chemistry and physics, a chain reaction is a process where the products of a reaction initiate further reactions of the same kind, creating a self-sustaining sequence. This can occur through stages: initiation, where a reactive intermediate is formed; propagation, where the intermediate reacts with reactants to produce products and another intermediate; and termination, which stops the reaction.1

A key concept in chain reactions is the "chain carrier," which is the reactive intermediate that propagates the reaction. These carriers can be atoms, ions, or molecular fragments. In some cases, like polymerization, these chain carriers are called radicals, which contain an unpaired electron. Branching chain reactions can accelerate rapidly, sometimes leading to explosions. Nuclear chain reactions, such as those in nuclear reactors or bombs, involve the splitting of atomic nuclei initiated by neutrons.12