Free-Radical Substitution

What happens in free radical substitution

Hydrogen atom gets substituted by a halogen

What conditions are needed for this reaction to happen

UV light

What happens in the initiation step

Halogen bond is broken by UV energy to form two radicals

What are radicals

Atoms, molecules or ions with unpaired electrons, making them highly reactive

What happens in the propagation step

The radicals create further radicals in a chain reaction

What is homolytic fission and what bond breaks homolytically

Where each atom gets one electron from the covalent bond - C-H bond

What free radical is produced

Alkyl free fradical

What can the alkyl do after reacting

It can attack another chlorine/bromine molecule to form a halogenoalkane and regenerate the chlorine/bromine free radical

What happens in the termination step

Chain reaction stops due to two free radicals reacting and forming a single unreactive molecule

What could possibly form in the termination step

Multiple products, depending on the radicals involved

What may happen if there is enough chlorine/bromine present

All the hydrogens in the alkane will eventually get substituted