Addition Reaction
Definition and meaning of Addition Reaction in chemistry.
An addition reaction is a type of chemical reaction in which two or more molecules combine to form a single product by adding across a double or triple bond. The bond is broken, and the atoms attach directly to the carbon atoms that were previously bonded together.
In more detail
Addition reactions are fundamental in organic chemistry and occur when reactants attach to unsaturated compounds (alkenes or alkynes). The reaction breaks the pi bond while keeping the sigma bond intact, allowing the attacking species to add to both carbon atoms. These reactions can be catalyzed by heat, light, or catalysts depending on the reactants involved. Addition reactions are economically important, used in the production of plastics, pharmaceuticals, and many industrial chemicals.
Key facts
| Field | Organic Chemistry |
|---|---|
| Requires | Unsaturated compounds (C=C or C≡C) |
| Product Count | Single product from multiple reactants |
| Common Type | Bromination, hydrogenation, hydration |
The bromination of ethene is a classic addition reaction. When ethene (C2H4) reacts with bromine (Br2), the double bond breaks and bromine atoms add to both carbons, forming 1,2-dibromoethane (C2H4Br2).
Frequently asked questions
What is the difference between addition and substitution reactions?
Addition reactions add atoms across a double or triple bond, creating one product from multiple reactants. Substitution reactions replace atoms or groups in a molecule without breaking double or triple bonds.
Can addition reactions occur with saturated compounds?
No, addition reactions require unsaturated compounds (those with C=C or C≡C bonds). Saturated compounds typically undergo substitution or elimination reactions instead.