An organic (alkyl-radical) chemical species is highly reactive and contains one unpaired electron in unhybridized orbitals.

It can also be represented by a dot. The number of alkyl group attached to an organic radical is what determines whether it is primary, secondary or tertiary. As the alkyl substituents increase at radical carbons, organic radical stability increases. This can be affected by resonance, inductive effect, and the nature of substituents.

You can classify organic radicals based on how many alkyl substitutes are present on the carbon-radical.

Primary organic radicals

Secondary organic radicals

Tertiary organic acids

Resonance:

A conjugated molecule is one pair of electrons, or pi electrons, that moves through sigma bonds within the molecule. This can lead to different arrangements of electrons (resonance contributors) for the same molecules. This is known as a resonance. It is, for example:

Stability of organic radiations:

As the substitution rate at radical carbon increases, organic radical stability is higher. Resonance can increase its stability (more double bond conjugation means a more stable structure).