The minimum number of carbon atoms that must be present in an alkene is

Alkenes are the carbon compounds with at least one double covalent bond between their carbon atoms. Double covalent bonds are formed when each atom contributes two electrons. Carbon cannot form a double covalent bond with hydrogen as hydrogen has only one valence electron. Therefore, alkene containing one carbon (i.e. methane) does not exist. The minimum number of carbon atoms that must be present in an alkene is two. Ethene (C₂H₄) is the simplest alkene containing two carbon atoms.