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formic acid

(Encyclopedia)formic acid or methanoic acid mĕthˌənōˈĭk [key], HCO2H, a colorless, corrosive liquid with a sharp odor; it boils at 100.7℃ and solidifies at 8.4℃. It has the lowest molecular weight and is ...

flame test

(Encyclopedia)flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt ...

naproxen

(Encyclopedia)naproxen and naproxen sodium, potent nonsteroidal anti-inflammatory drugs (NSAID) used to alleviate the minor pain of arthritis, menstruation, headaches, and the like, and to reduce fever. Along with ...

viscose process

(Encyclopedia)viscose process vĭsˈkōs [key], method widely used for the commercial preparation of rayon. Cellulose, prepared from either wood pulp or, less commonly, cotton linters, is treated with sodium hydrox...

ion, in chemistry

(Encyclopedia)ion, atom or group of atoms having a net electric charge. Ionization has many applications. Vapor lamps and fluorescent lamps take advantage of the light given off when positive ions recombine with ...

saccharin

(Encyclopedia)saccharin săkˈərĭn [key], C7H5NSO3, white, crystalline, aromatic compound. It was discovered accidentally by I. Remsen and C. Fahlberg in 1879. Pure saccharin tastes several hundred times as sweet...

alkali metals

(Encyclopedia)alkali metals, metals found in Group 1 of the periodic table. Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univ...

Salinas Grandes

(Encyclopedia)Salinas Grandes sälēˈnäs gränˈdās [key], salt desert, c.3,200 sq mi (8,290 sq km), in Córdoba and Santiago del Estero provs., N Argentina. The Córdoba-Tucumán RR crosses the desert. Sodium a...

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