What type of reaction is used to convert an alkene to a dihaloalkane?

The conversion of an alkene to a dihaloalkane involves the addition of halogens, such as bromine (Br2) or chlorine (Cl2), across the double bond of the alkene. This process is classified as an addition reaction because two atoms or groups (in this case, halogen atoms) are added to the carbon atoms involved in the double bond, effectively converting the unsaturated alkene into a saturated dihaloalkane.

In this reaction, the double bond is broken, and halogen atoms are introduced to the carbon atoms that were initially part of the double bond. As a result, the product consists of two halogen atoms attached to the alkene’s carbon framework, hence forming a dihaloalkane. This addition reaction is typically characterized by the formation of a cyclic bromonium or chloronium ion intermediate, which further leads to the nucleophilic attack by another halide ion, resulting in the final dihaloalkane product.

This reaction is distinct from substitution reactions, which involve replacing one atom or group in a molecule with another, as well as oxidation reactions, which involve the addition of oxygen or the removal of hydrogen or electrons from a substance. In summary, the correct answer highlights the essential nature of