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sodium nitrate

(Encyclopedia)sodium nitrate, chemical compound, NaNO3, a colorless, odorless crystalline compound that closely resembles potassium nitrate (saltpeter or niter) in appearance and chemical properties. It is soluble ...

sperm oil

(Encyclopedia)sperm oil, liquid wax obtained from the sperm whale, or cachalot, and related marine mammals. It flows readily, is clear, and varies in color from pale yellow to brownish yellow. Chemically it is not ...

cooking

(Encyclopedia)cooking, the process of using heat to prepare foods for consumption. Many common cooking methods involve the use of oil. Frying is cooking in hot oil; sautéing is cooking in a small amount of oil; st...

specific gravity

(Encyclopedia)specific gravity, ratio of the weight of a given volume of a substance to the weight of an equal volume of some reference substance, or, equivalently, the ratio of the masses of equal volumes of the t...

Oberth, Hermann Julius

(Encyclopedia)Oberth, Hermann Julius, 1894–1989, Austro-German astronautical pioneer, b. Hermannstadt, Austria-Hungary (now Sibiu, Romania). Beginning his studies in astronautics before World War I, he first prop...

rennet

(Encyclopedia)rennet, substance containing rennin, an enzyme having the property of clotting, or curdling, milk. It is used in the making of cheese and junket. Rennet is obtained from the stomachs of young mammals ...

enthalpy

(Encyclopedia)enthalpy ĕnˈthălpē [key], measure of the heat content of a chemical or physical system; it is a quantity derived from the heat and work relations studied in thermodynamics. As a system changes fro...

argon

(Encyclopedia)argon ärˈgŏn [key] [Gr.,=inert], gaseous chemical element; symbol Ar; at. no. 18; at. wt. 39.948; m.p. −189.2℃; b.p. −185.7℃; density 1.784 grams per liter at STP; valence 0. Argon is a col...

oxygen

(Encyclopedia)oxygen, gaseous chemical element; symbol O; at. no. 8; interval in which at. wt. ranges 15.99903–15.99977; m.p. −218.4℃; b.p. −182.962℃; density 1.429 grams per liter at STP; valence −2. T...

divination

(Encyclopedia)divination, practice of foreseeing future events or obtaining secret knowledge through communication with divine sources and through omens, oracles, signs, and portents. It is based on the belief in r...