A<unk>  is any chemical reaction involving<unk><unk> s. This reaction type is abundant in organic reactions.
Two pioneering studies into<unk> s have been the discovery of the triphenylmethyl<unk>  by Moses Gomberg (1900) and the lead-mirror experiment  described by Friedrich Paneth in 1927. In this last experiment tetramethyllead is decomposed at elevated temperatures to methyl<unk> s and elemental lead in a quartz tube. The gaseous methyl<unk> s are moved to another part of the chamber in a carrier gas where they react with lead in a mirror film which slowly disappears.
When<unk>  reactions are part of organic synthesis the<unk> s are often generated from<unk>  initiators such as peroxides or azobis compounds. Many<unk>  reactions are chain reactions with a chain initiation step, a chain propagation step and a chain termination step. Reaction inhibitors slow down a<unk>  reaction.<unk>  reactions occur frequently in the gas phase, are often initiated by light, are rarely acid or base catalyzed an are not dependent on polarity of the reaction medium . Reactions are also similar whether in the gas phase or solution phase .
Free radical reaction
Organic redox reaction
Exothermic reaction
Organic reaction
Degenerate energy level
Di-pi-methane rearrangement
Dielectric relaxation
Condensation reaction