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Kapitza, Peter

(Encyclopedia)Kapitza, Peter käˈpētsə [key], 1894–1984, Russian physicist, educated at the polytechnic institute of Petrograd (now St. Petersburg) and at Cambridge. He developed equipment (for a laboratory at...

lactic acid

(Encyclopedia)lactic acid, CH3CHOHCO2H, a colorless liquid organic acid. It is miscible with water or ethanol. Lactic acid is a fermentation product of lactose (milk sugar); it is present in sour milk, koumiss, leb...

plaster casting

(Encyclopedia)plaster casting, as a sculpture process, is of three kinds. One employs a waste mold, another a piece mold (both plaster of paris), and the third a gelatin mold; all reproduce the original clay or wax...

butyric acid

(Encyclopedia)butyric acid byo͞otənōˈĭk [key], CH3CH2CH2CO2H, viscous, foul-smelling, liquid carboxylic acid; m.p. about −5℃; b.p. 163.5℃. It is miscible with water, ethanol, and ether. It is a low molec...

benzaldehyde

(Encyclopedia)benzaldehyde bĕnˌzēnkärˈbənəl [key], C6H5CHO, colorless liquid aldehyde with a characteristic almond odor. It boils at 180℃, is soluble in ethanol, but is insoluble in water. It is formed by ...

tetraethyl lead

(Encyclopedia)tetraethyl lead tĕtˌrəĕthˈəl [key], (C2H5)4Pb, viscous, colorless, poisonous liquid. It is an organometallic compound prepared by reacting ethyl chloride with a sodium-lead alloy. When added to ...

pyridine

(Encyclopedia)pyridine ăzˈēn [key], C5H5N, colorless, flammable, toxic liquid with a putrid odor. It melts at −42℃ and boils at 115.5℃. Chemically, it is a heterocyclic aromatic tertiary amine (see under a...

Bergius, Friedrich Karl Rudolf

(Encyclopedia)Bergius, Friedrich Karl Rudolf, 1884–1949, German chemist, Ph.D. Univ. of Leipzig, 1907. In 1910, Bergius set up a laboratory to carry out his research and in 1914 transferred the operation to the E...

zakat

(Encyclopedia)zakat zə-kätˈ [key] [Arab.,=purification], Islamic religious tax, one of the five basic requirements (arkan or “pillars”) of Islam. All adult Muslims of sound mind and body with a set level of ...

exposition

(Encyclopedia)exposition or exhibition, term frequently applied to an organized public fair or display of industrial and artistic productions, designed usually to promote trade and to reflect cultural progress. Exp...