Final answer:
The reaction described is an addition reaction.
Step-by-step explanation:
The reaction described is an addition reaction.
An addition reaction is a reaction in which an atom or molecule is added to an unsaturated molecule, making a single product. It can be thought of as adding a molecule across the double bond or triple bond of an alkene or alkyne. This type of reaction is commonly seen in organic chemistry.
For example, in an addition reaction between an alkene and a halogen, such as the reaction between ethene and chlorine, the double bond in the alkene is broken and each carbon atom forms a single bond with a chlorine atom, resulting in the formation of a product with no double bond.