addíció

Addíció is a term used in chemistry to describe a type of chemical reaction where two or more molecules combine to form a larger molecule. This typically occurs across a double or triple bond, breaking the pi bonds and forming new sigma bonds. The overall process is usually exothermic, releasing energy. A common example is the addition of hydrogen to an alkene or alkyne to form an alkane, a reaction known as hydrogenation. Other reactants that can undergo addition reactions include halogens, hydrogen halides, and water. The regioselectivity of addition reactions, where a non-symmetrical reagent adds to a non-symmetrical multiple bond, is often governed by Markovnikov's rule, which states that the hydrogen atom will attach to the carbon atom that already has the most hydrogen atoms. In contrast, anti-Markovnikov addition can occur under specific conditions, such as in the presence of peroxides. Addition reactions are fundamental in organic synthesis, allowing for the creation of a wide variety of organic compounds from simpler precursors. They play a crucial role in the industrial production of many chemicals and materials.