Electrophilic addition reaction

In an addition reaction in organic chemistry, 2 or more molecules are joined together. This follows the scheme A + B → C. A distinction is made between a nucleophilic and an electrophilic addition reaction. The term nucleophilic or electrophilic refers to the molecule or atom that attacks the carbon chain.

In this experiment, bromine is used as an electrophile to add to the double bond of cyclohexene. The students can see from the decolourisation of the solutions that an electrophilic addition reaction only takes place when bromine comes into contact with a molecule with a double bond.