An addition reaction, in organic chemistry, is in its simplest terms an organic reaction where two or more molecules combine to form a larger one.
Addition reactions are limited to chemical compounds that have multiply bonded atoms, such as molecules with carbon-carbon double bonds, i.e., alkenes, or with triple bonds, i.e., alkynes. Also included are molecules containing carbon—hetero double bonds like those with carbonyl (C=O) groups or those with imine (C=N) groups. Read more on – Wikipedia
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