What is an alkene?

An alkene is an unsaturated hydrocarbon, which means it contains a carbon-carbon double bond (C=C) in its structure. They are a family of organic compounds and have the general molecular formula CnH2n, where n represents the number of carbon atoms.

The presence of the carbon-carbon double bond in alkenes makes them more reactive compared to alkanes, which have only single bonds between carbon atoms. The double bond consists of one sigma bond and one pi bond. Apart from the double bond, the remaining carbon atoms are bonded to hydrogen atoms or other carbon atoms.

The IUPAC nomenclature for alkenes consists of adding the suffix "-ene" to the base name of the corresponding alkane. The carbon atom count is used to determine the base name, and the position of the double bond is specified by a number. For example, in the case of CH2=CH2, it is called ethene, as it has two carbon atoms in the molecule.

Here are a few examples of alkenes: 1. Ethene: \( CH_2=CH_2 \). It has two carbon atoms and a double bond between them. 2. Propene: \( CH_2=CH-CH_3 \). It has three carbon atoms with a double bond between the first and second carbon atoms. 3. Butene: \( CH_2=CH-CH_2-CH_3 \). It has four carbon atoms with a double bond between the first and second carbon atoms. Remember that the position of the double bond may vary, so there can be isomers of alkenes with the same molecular formula but different structures, such as: 1. 1-Butene: \( CH_2=CH-CH_2-CH_3 \). The double bond is between the first and second carbon atoms. 2. 2-Butene: \( CH_3-CH=CH-CH_3 \). The double bond is between the second and third carbon atoms.