Chemistry – Organic chemistry - Formulae, functional groups and terminology | e-Consult

Unsaturated compounds contain one or more double or triple bonds between carbon atoms. These bonds are not single bonds, which are formed by sharing only one pair of electrons. Double bonds involve sharing two pairs of electrons, and triple bonds involve sharing three pairs of electrons.

The presence of these multiple bonds means that electrons are more readily available for reacting with other substances. Single bonds are less reactive because the electrons are more tightly held. The pi bonds in double and triple bonds are weaker than sigma bonds in single bonds, making them easier to break and thus more susceptible to chemical reactions like addition reactions. Therefore, unsaturated compounds are generally more reactive than saturated compounds.