Potassium — (pronEng|pəˈtæsiəm) is a chemical element. It has the symbol K ( la. kalium, from ar. qalīy), atomic number 19, and atomic mass 39.0983. The name potassium comes from the word potash , as potassium was first isolated from potash. Potassium is a… … Wikipedia
POTASSIUM — Le potassium, troisième élément de ce groupe, possède les propriétés caractéristiques des métaux alcalins. Il a été découvert en 1807 par Humphry Davy lors de la réduction électrolytique de la potasse caustique fondue (KOH). Son symbole chimique… … Encyclopédie Universelle
Potassium — Argon ← Potassium → Calcium Na … Wikipédia en Français
Potassium — Po*tas si*um, n. [NL. See {Potassa}, {Potash}.] (Chem.) An Alkali element, occurring abundantly but always combined, as in the chloride, sulphate, carbonate, or silicate, in the minerals sylvite, kainite, orthoclase, muscovite, etc. Atomic weight … The Collaborative International Dictionary of English
Potassĭum — Potassĭum, soviel wie Kalium … Meyers Großes Konversations-Lexikon
potassium — metallic element, 1807, coined by English chemist Sir Humphrey Davy (1778 1829) from Mod.L. potassa, Latinized form of POTASH (Cf. potash) (q.v.). Davy first isolated it from potash. Symbol K is from L. kalium potash, from Arabic al qaliy the… … Etymology dictionary
potassium — ► NOUN ▪ a soft silvery white reactive metallic element of the alkali metal group. ORIGIN from POTASH(Cf. ↑potash) … English terms dictionary
potassium — [pə tas′ē əm] n. [ModL: so named (1807) < potassa < Du potasch, POTASH, by Humphrey DAVY Sir Humphry, who first isolated it from potash] a soft, silver white, waxlike metallic chemical element, one of the alkali metals, that oxidizes… … English World dictionary
potassium — /peuh tas ee euhm/, n. Chem. a silvery white metallic element that oxidizes rapidly in the air and whose compounds are used as fertilizer and in special hard glasses. Symbol: K; at. wt.: 39.102; at. no.: 19; sp. gr.: 0.86 at 20°C. [1800 10; < NL; … Universalium
Potassium 40 — Le potassium 40, noté 40K, est l isotope du potassium dont le nombre de masse est égal à 40 : son noyau atomique compte 19 protons et 21 neutrons. C est un radioisotope du milieu naturel qu on trouve par exemple dans la bauxite… … Wikipédia en Français