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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...

salicylate

(Encyclopedia)salicylate səlĭsˈəlātˌ [key], any of a group of analgesics, or painkilling drugs, that are derivatives of salicylic acid. The best known is acetylsalicylic acid, or aspirin. Now often made synth...

tungsten

(Encyclopedia)tungsten tŭngˈstən [key] [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410℃; b.p. 5,660℃; sp. gr. 19.3 at 20℃; valence +2, +3, +4, +5, or...

Lydd

(Encyclopedia)Lydd lĭd [key], town (1991 pop. 4,721), Kent, SE England. A military training center, Lydd gave its name to lyddite (picric acid), an explosive that was tested at the military camp there in 1888. Lyd...

tartar

(Encyclopedia)tartar or argol ärˈgəl [key], impure potassium hydrogen tartrate deposited as a crust in fermenting vessels during wine making. When purified, it yields cream of tartar. Tartar is the chief natural...

Prout, William

(Encyclopedia)Prout, William, 1785–1850, English chemist and physician. Prout's hypothesis, advanced in 1815–16, suggested that atomic weights of elements are multiples of that of hydrogen and that elements are...

zinc sulfate

(Encyclopedia)zinc sulfate, chemical compound ZnSO4, a very water soluble, transparent, colorless, crystalline compound. It is commonly used as the heptahydrate, ZnSO4·7H2O, and is commonly called white vitriol; i...

atropine

(Encyclopedia)atropine ătˈrəpēn, –pĭn [key], alkaloid drug derived from belladonna and other plants of the family Solanaceae (nightshade family). Available either as the tincture or extract of belladonna, or...

myoglobin

(Encyclopedia)myoglobin mīˌəglōˈbĭn [key], protein molecule isolated from the cells of vertebrate skeletal muscle that is both a structural and functional relative of hemoglobin, the oxygen-transport protein ...