Alkenes are organic compounds made up of carbon and hydrogen atoms with one or more carbon- carbon double bonds. Their names end with ‘-ene’ and their physical state depends on their number of carbon atoms. Alkenes containing two to four carbon atoms usually exist as gases. Examples include ethane and propene.
Those with carbon atoms between five and sixteen generally exist as liquids and those with carbon atoms in excess of seventeen tend to exist as waxy solids. Examples can be found in paraffin wax which is a material for making candles. They are generally soluble in organic solvents such as acetone or benzene.
Alkenes are used for a wide variety of purposes, the most notable being their role in the manufacture of plastics and rubber. Alkenes are unsaturated hydrocarbons, they are insoluble in water and their use in pharmaceutical preparations is very restricted as a result of their toxicity to the body. They are more commonly used in industry as raw materials for the manufacturing of alcohols and aldehydes.