The general formula for the alkenes is CnH2n, where n is the number of carbon atoms in the molecule.
The formula will be C10H20. This is because n = 10. So, 2n = (2 × 10) = 20.
Hexene is an alkene. Its molecules contain 6 carbon atoms. Predict the molecular formula of hexene.
The formula will be C6H12.
The table shows four alkenes, their molecular formulae and their structures.
The ball and stick models on the right show that the covalent bonds are not really at angles of 90°, as shown in the structures.
The alkenes are unsaturated hydrocarbons:
The C=C bond is the functional group in the alkenes. It is responsible for the typical reactions of alkenes.