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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...

mordant

(Encyclopedia)mordant môrˈdənt [key] [Fr.,=biting], substance used in dyeing to fix certain dyes (mordant dyes) in cloth. Either the mordant (if it is colloidal) or a colloid produced by the mordant adheres to t...

urine

(Encyclopedia)urine, clear, amber-colored fluid formed by the kidneys that carries metabolic wastes out of the body (see urinary system). As the blood circulates it collects excretory products from the tissues and ...

tourmaline

(Encyclopedia)tourmaline to͝orˈməlĭn, –lēn [key], complex borosilicate mineral with varying amounts of aluminum, iron, magnesium, sodium, lithium, potassium, and sometimes other elements, used as a gem. It o...

corticosteroid drug

(Encyclopedia)corticosteroid drug kôrˌtəkōstârˈoid [key], any one of several synthetic or naturally occurring substances with the general chemical structure of steroids. They are used therapeutically to mimic...

carbonate

(Encyclopedia)carbonate kärˈbənātˌ, –nət [key], chemical compound containing the carbonate radical or ion, CO3−2. Most familiar carbonates are salts that are formed by reacting an inorganic base (e.g., a ...

mineral water

(Encyclopedia)mineral water, spring water containing various mineral salts, especially the carbonates, chlorides, phosphates, silicates, sulfides, and sulfates of calcium, iron, lithium, magnesium, potassium, sodiu...

oxalic acid

(Encyclopedia)oxalic acid ĕthˌāndīōĭk [key], HO2CCO2H, a colorless, crystalline organic carboxylic acid that melts at 189℃ with sublimation. Oxalic acid and oxalate salts are poisonous. Oxalic acid is found...

silver chloride

(Encyclopedia)silver chloride, chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate (“h...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...