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Physical Chemistry

Abstraction Reaction

Definition and meaning of Abstraction Reaction in chemistry.

An abstraction reaction is a reaction in which one species removes an atom, most often a hydrogen atom, from another molecule. Hydrogen abstraction by free radicals is a key step in many chain reactions.

In more detail

In a typical hydrogen abstraction, a reactive radical pulls a hydrogen atom away from a stable molecule, forming a new bond to that hydrogen and leaving behind a new radical. This propagates radical chain reactions and is important in combustion, atmospheric chemistry, and the aging of plastics.

Key facts

Atom transferredUsually hydrogen
Common agentA free radical
Occurs inRadical chain reactions
FieldPhysical / organic chemistry
Example

In the chlorination of methane, a chlorine radical abstracts a hydrogen atom from methane, producing hydrogen chloride and a methyl radical.

Frequently asked questions

What is hydrogen abstraction?

It is an abstraction reaction in which a reactive species, usually a free radical, removes a hydrogen atom from another molecule, creating a new radical.

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