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carbon tetrachloride

(Encyclopedia)carbon tetrachloride tĕˌtrəklôrˌəmĕthˈān [key], CCl4, colorless, poisonous, liquid organic compound that boils at 76.8℃. It is toxic when absorbed through the skin or when inhaled. It react...

boron

(Encyclopedia)boron bōrˈŏn [key] [New Gr. from borax], chemical element; symbol B; at. no. 5; interval in which at. wt. ranges 10.806–10.821; m.p. about 2,300℃; sublimation point about 2,550℃; sp. gr. 2.3 ...

Chagai

(Encyclopedia)Chagai chäˈgī [key], town, W Pakistan, near the border with Afghanistan, on the trade route to Afghanistan and Iran. Pastoral Baluchi and Brahui inhabit the region, which is noted for its Oriental ...

freezing

(Encyclopedia)freezing, change of a substance from the liquid to the solid state. The temperature at which freezing occurs for a pure crystalline solid is called the freezing point and is a characteristic of the pa...

Liancourt Rocks

(Encyclopedia)Liancourt Rocks, Jap. Takeshima, Korean Dokdo or Tokdo, island group, 58 acres (23 hectares), in the SW Sea of Japan, roughly midway between the Japanese island of Honshu and the Korean peninsula. Con...

scheelite

(Encyclopedia)scheelite shāˈlīt, shēˈ– [key], heavy white or yellow mineral, calcium tungstate, CaWO4, crystallizing in the tetragonal system. It is found in granite pegmatites, in contact-metamorphic deposi...

pyrolusite

(Encyclopedia)pyrolusite pīˈrōlo͞ozīt [key], naturally occurring manganese dioxide, MnO2, a black mineral that crystallizes in the tetragonal system but is usually found in earthy or massive deposits. It is th...

pyrrhotite

(Encyclopedia)pyrrhotite pĭrˈətīt [key] or magnetic pyrites, bronze-yellow to bronze-red mineral, a sulfide of iron sometimes containing nickel. It tarnishes easily and is somewhat magnetic. It crystallizes in ...

Ouachita Mountains

(Encyclopedia)Ouachita Mountains, range of east-west ridges between the Arkansas and Red rivers, extending c.200 mi (320 km) from central Ark. into SE Okla. Magazine Mt. (c.2,800 ft/850 m high) is the tallest peak....

laetrile

(Encyclopedia)laetrile lāˈətrĭlˌ [key], name given to the chemical amygdalin, a substance derived from an extract of the kernels of many fruits, notably apricots, bitter almonds, and peaches. The idea that lae...