precipitation chemistry
41separation and purification — ▪ chemistry Introduction in chemistry, separation of a substance into its components and the removal of impurities. There are a large number of important applications in fields such as medicine and manufacturing. General principles… …
42surface coating — ▪ chemistry Introduction any mixture of film forming materials plus pigments, solvents, and other additives, which, when applied to a surface and cured or dried, yields a thin film that is functional and often decorative. Surface coatings… …
43isotopic fractionation — ▪ chemistry enrichment of one isotope relative to another in a chemical or physical process. Two isotopes of an element are different in weight but not in gross chemical properties, which are determined by the number of electrons. However,… …
44quantitative chemical analysis — ▪ chemistry branch of chemistry that deals with the determination of the amount or percentage of one or more constituents of a sample. A variety of methods is employed for quantitative analyses, which for convenience may be broadly… …
45hydrosphere — /huy dreuh sfear /, n. the water on or surrounding the surface of the globe, including the water of the oceans and the water in the atmosphere. [1885 90; HYDRO 1 + SPHERE] * * * Discontinuous layer of water at or near the Earth s surface. It… …
46Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
47Chemical reaction — Chemical reactions redirects here. For the 2007 television episode, see Chemical Reactions (Men in Trees). A thermite reaction using iron(III) oxide. The sparks …
48lake — lake1 /layk/, n. 1. a body of fresh or salt water of considerable size, surrounded by land. 2. any similar body or pool of other liquid, as oil. 3. (go) jump in the lake, (used as an exclamation of dismissal or impatience.) [bef. 1000; ME lak(e) …
49Lake — /layk/, n. Simon, 1866 1945, U.S. engineer and naval architect. * * * I Relatively large body of slow moving or standing water that occupies an inland basin. Lakes are most abundant in high northern latitudes and in mountain regions, particularly …
50climate change — Introduction periodic modification of Earth s climate brought about as a result of changes in the atmosphere as well as interactions between the atmosphere and various other geologic, chemical, biological, and geographic factors within the Earth …
