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Nikolay Nikolaevich Semenov
1896–1986 · Russia · Born in the 1800s
Nobel Chemistry 1956
Soviet physical chemist who created the theory of branched chain reactions, explaining explosions, combustion and oxidation kinetics.
Nobel-winning work
Semenov founded the theory of chain reactions, showing that reactive intermediates can branch a reaction so that one event triggers many more. His concepts of chain branching and termination explained explosions, combustion and oxidation processes, transforming the understanding of chemical reaction mechanisms — a prize shared with Cyril Hinshelwood.
Fields
Related topics
Reaction rate, reaction order
Measuring how fast concentrations change, and how the empirical order of a reaction is read from its concentration–time behaviour.
Complex reaction mechanisms, catalysis
Building rate laws from elementary steps, steady-state and rate-determining-step approximations, chain reactions, and how catalysts open alternative pathways.