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tetany

(Encyclopedia)tetany tĕtˈənē [key], condition of mineral imbalance in the body that results in severe muscle spasms. Tetany occurs when the concentration of calcium ions (Ca++) in extracellular fluids such as p...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

Maurer, Ion Gheorghe

(Encyclopedia)Maurer, Ion Gheorghe yôn gāôrˈgā [key], 1902–2000, Romanian statesman. A lawyer, he defended Romanian Communists in the 1930s and later became (1945) a member of the central committee of the Co...

common-ion effect

(Encyclopedia)common-ion effect, decrease in solubility of an ionic salt, i.e., one that dissociates in solution into its ions, caused by the presence in solution of another solute that contains one of the same ion...

field-ion microscope

(Encyclopedia)field-ion microscope: see microscope. ...

potassium hydrogen tartrate

(Encyclopedia)potassium hydrogen tartrate: see cream of tartar. ...

sodium hydrogen carbonate

(Encyclopedia)sodium hydrogen carbonate: see sodium bicarbonate. ...

Caragiale, Ion Luca

(Encyclopedia)Caragiale, Ion Luca yŏn lo͞oˈkä käräjäˈlĭ [key], 1853–1912, Romanian playwright and author. Romania's foremost dramatist, his works sharply satirized Romanian society. His masterpiece, A Lo...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

Le Châtelier's principle

(Encyclopedia)Le Châtelier's principle, chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components...