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carbide

(Encyclopedia)carbide, any one of a group of compounds that contain carbon and one other element that is either a metal, boron, or silicon. Generally, a carbide is prepared by heating a metal, metal oxide, or metal...

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...

Bon, Cape

(Encyclopedia)Bon, Cape ädärˈ [key], peninsula, NE Tunisia, projecting c.50 mi (80 km) into the Mediterranean Sea toward Sicily. Cape Bon, the eastern terminus of the Saharan Atlas Mts., is a hilly, fertile regi...

periodic table

(Encyclopedia)CE5 periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arrange...

pump

(Encyclopedia)pump, device to lift, transfer, or increase the pressure of a fluid (gas or liquid) or to create a vacuum in an enclosed space by the removal of a gas (see vacuum pumps under vacuum). The centrifugal ...

radiator

(Encyclopedia)radiator, device used to heat an area surrounding it or to cool a fluid circulating within it. The familiar radiators of steam and hot water heating systems in buildings are misnamed, as they operate ...

low-temperature physics

(Encyclopedia)low-temperature physics, science concerned with the production and maintenance of temperatures much below normal, down to almost absolute zero, and with various phenomena that occur only at such tempe...

molecular weight

(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...

chemical equation

(Encyclopedia)chemical equation, group of symbols representing a chemical reaction. There are a number of other symbols used in chemical equations. A symbol written above or below the reaction arrow indicates spe...

jet propulsion

(Encyclopedia)CE5 Types of jet engines: In the propeller-driven turbine a stream of high-velocity gases provides the power to drive the turbine and turn the propeller. In the jet-driven turbine the stream of gas...