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barium

(Encyclopedia)barium bârˈēəm [key] [Gr.,=heavy], metallic chemical element; symbol Ba; at. no. 56; at. wt. 137.327; m.p. 725℃; b.p. 1,640℃; sp. gr. 3.5 at 20℃; valence +2. Barium is a soft, silver-white, ...

electrolyte

(Encyclopedia)electrolyte ĭlĕkˈtrəlītˌ [key], electrical conductor in which current is carried by ions rather than by free electrons (as in a metal). Electrolytes include water solutions of acids, bases, or s...

depilatory

(Encyclopedia)depilatory dĭpĭlˈətôrˌē [key], substance used to remove hair. In preparing hides for tanning, lime is the chief depilatory. For the removal of superfluous hair from the human body, metal sulfid...

Clausius, Rudolf Julius Emanuel

(Encyclopedia)Clausius, Rudolf Julius Emanuel ro͞oˈdôlf yo͞oˈlyo͝os āmäˈno͞oĕl klouˈzēo͝os [key], 1822–88, German mathematical physicist. A pioneer in the science of thermodynamics, he introduced th...

electrochemistry

(Encyclopedia)electrochemistry, science dealing with the relationship between electricity and chemical changes. Of principal interest are the reactions that take place between electrodes and the electrolytes in ele...

sodium

(Encyclopedia)sodium, a metallic chemical element; symbol Na [Lat. natrium]; at. no. 11; at. wt. 22.98977; m.p. 97.81℃; b.p. 892.9℃; sp. gr. 0.971 at 20℃; valence +1. Sodium is a soft, silver-white metal. Ext...

strontium

(Encyclopedia)strontium strŏnˈshēəm [key] [from Strontian, a Scottish town], a metallic chemical element; symbol Sr; at. no. 38; at. wt. 87.62; m.p. 769℃; b.p. 1,384℃; sp. gr. 2.6 at 20℃; valence +2. Stro...

electrode

(Encyclopedia)electrode, terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit. In most familiar circuits current is carried by metallic conductors, but in som...

hydrogen peroxide

(Encyclopedia)hydrogen peroxide, chemical compound, H2O2, a colorless, syrupy liquid that is a strong oxidizing agent and, in water solution, a weak acid. It is miscible with cold water and is soluble in alcohol an...

refining

(Encyclopedia)refining, any of various processes for separating impurities from crude or semifinished materials. It includes the finer processes of metallurgy, the fractional distillation of petroleum into its comm...

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