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element

(Encyclopedia)CE5 element, in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means o...

sulfonic acid

(Encyclopedia)sulfonic acid səlfŏnˈĭk [key], organic compound containing the functional group RSO2OH, which consists of a sulfur atom, S, bonded to a carbon atom that may be part of a large aliphatic or aromati...

halogen

(Encyclopedia)halogen hălˈəjĕn [key] [Gr.,=salt-bearing], any of the chemically active elements found in Group 17 of the periodic table; the name applies especially to fluorine (symbol F), chlorine (Cl), bromin...

molecule

(Encyclopedia)molecule mŏlˈəkyo͞ol [key] [New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, a...

insecticides

(Encyclopedia)insecticides, chemical, biological, or other agents used to destroy insect pests; the term commonly refers to chemical agents only. The liabilities of chemical insecticides have encouraged interest ...

Tooele

(Encyclopedia)Tooele to͞oĭlˈə [key], city (1990 pop. 13,887), seat of Tooele co., N central Utah, a rapidly growing suburb of Salt Lake City, in a farm area; inc. 1853. A major source of employment is the Tooel...

metabolite

(Encyclopedia)metabolite, organic compound that is a starting material in, an intermediate in, or an end product of metabolism. Starting materials are substances, usually small and of simple structure, absorbed by ...

soap

(Encyclopedia)soap, a cleansing agent. It cleanses by lowering the surface tension of water, by emulsifying grease, and by absorbing dirt into the foam. Ancient peoples are believed to have employed wood ashes and ...

solution

(Encyclopedia)CE5 Solubility curves solution, in chemistry, homogeneous mixture of two or more substances. The dissolving medium is called the solvent, and the dissolved material is called the solute. A solutio...

photographic processing

(Encyclopedia)photographic processing, set of procedures by which the latent, or invisible, image produced when a photographic film is exposed to light is made into a permanent visible image. The negative may b...