alkeneissä

Alkenes are a class of organic compounds that contain at least one carbon-carbon double bond. The general formula for acyclic alkenes with one double bond is CnH2n. This distinguishes them from alkanes, which have the general formula CnH2n+2 and only single bonds between carbon atoms. The presence of the pi bond in the double bond makes alkenes more reactive than alkanes, particularly in addition reactions.

The simplest alkene is ethene (C2H4), also known as ethylene, which has a double bond between two carbon atoms. Propene (C3H6) is another common alkene. As the number of carbon atoms increases, structural isomers become possible, meaning there can be different arrangements of atoms with the same molecular formula. For example, butene (C4H8) exists as but-1-ene and but-2-ene, with but-2-ene further existing as cis- and trans- isomers due to restricted rotation around the double bond.

Alkenes are important industrial chemicals and are used as monomers in the production of polymers like polyethylene and polypropylene. They are also intermediates in the synthesis of various organic compounds, including alcohols, aldehydes, and carboxylic acids, through reactions such as hydration, oxidation, and halogenation. The reactivity of the double bond is key to their utility in organic chemistry.