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kinetin

(Encyclopedia)kinetin kīˈnətĭn [key], one of a group of chemically similar plant hormones, the cytokinins, that promote cell division. In some instances kinetin acts together with another hormone, indoleacetic ...

cream of tartar

(Encyclopedia)cream of tartar, white crystalline powder. Chemically it is potassium hydrogen tartrate, KC4H5O6, the acidic potassium salt of tartaric acid. It is used as the leavening agent in baking powders. An im...

Roebuck, John

(Encyclopedia)Roebuck, John, 1718–94, English physician, chemist, and inventor. He acted as a chemical consultant to local industries in Birmingham and invented the lead chamber process of manufacturing sulfuric ...

sodium benzoate

(Encyclopedia)sodium benzoate or benzoate of soda, chemical compound, C6H5CO2Na, colorless or white crystalline, aromatic compound; the sodium salt of benzoic acid. It is soluble in water and is used as a preservat...

ethanol

(Encyclopedia)ethanol ĕthˈənōlˌ [key] or ethyl alcohol, CH3CH2OH, a colorless liquid with characteristic odor and taste; commonly called grain alcohol or simply alcohol. Ethanol is used extensively as a solv...

oxidation and reduction

(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...

Wheeldon, Christopher

(Encyclopedia)Wheeldon, Christopher, 1973–, British ballet dancer and choreographer, studied Royal Ballet School, London. An outstanding contemporary classicist, Wheeldon creates dances that are lyrical, witty, s...

Lappeenranta

(Encyclopedia)Lappeenranta läpˈpānränˌtä [key], Swed. Villmanstrand, city (1998 pop. 57,374), Southern Finland prov., SE Finland, on Lake Saimaa. It is an important trade and industrial center, with sulfuric ...

antacid

(Encyclopedia)antacid, any one of several basic substances that counteract stomach acidity (see stomach). Antacids are used by physicians to treat hyperchlorhydria, i.e., the excessive production of hydrochloric ac...

hardpan

(Encyclopedia)hardpan, condition of the soil or subsoil in which the soil grains become cemented together by such bonding agents as iron oxide and calcium carbonate, forming a hard, impervious mass. It is disadvant...