A chemical reaction is a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Chemistry is the science of the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes. Chemistry is concerned with the properties of atoms and the laws governing their combinations.
Chemical industry, complex of processes, operations, and organizations engaged in the manufacture of chemicals and their derivatives. Raw materials include fossil fuels and inorganic chemicals. An average chemical product is passed from factory to factory several times before it emerges into the market.
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The Chemical Brothers, a British deejay-producer duo who pioneered the big beat dance music genre in the 1990s with such singles as ‘Chemical Beats,’ ‘Block Rockin’ Beats,’ ‘Loops of Fury,’ and ‘Setting Son.’ They remained popular into the 21st century. Learn more about their background, music, and career.
Helium is a chemical element, an inert gas of Group 18 (noble gases) of the periodic table. The second lightest element, helium is a colorless, odorless, and tasteless gas that becomes liquid at -268.9 degrees Celsius. The boiling and freezing points of helium are lower than those of any other known substance.
A carbohydrate is a naturally occurring compound, or a derivative of such a compound, with the general chemical formula C x (H 2 O) y, made up of molecules of carbon (C), hydrogen (H), and oxygen (O). Carbohydrates are the most widespread organic substances and play a vital role in all life.