n.
Science that deals with the properties, composition, and structure of substances ( element s and compound s), the reactions and transformations they undergo, and the energy released or absorbed during those processes.
Often called the "central science," chemistry is concerned with atom s as building blocks (rather than with the subatomic domain; see nuclear physics , quantum mechanics ), with everything in the material world, and with all living things. Branches of chemistry include inorganic (see inorganic compound ), organic (see organic compound ), physical , and analytical (see analysis ) chemistry; biochemistry ; electrochemistry ; and geochemistry . Chemical engineering (applied chemistry) uses the theoretical and experimental information obtained in chemistry to build chemical plants and make useful products.