rubidium

ru·bid·i·um  (r-bd-m)

n. Symbol Rb

A soft silvery-white metallic element of the alkali group that ignites spontaneously in air and reacts violently with water, used in photocells and in the manufacture of vacuum tubes. Atomic number 37; atomic weight 85.47; melting point 38.89°C; boiling point 688°C; specific gravity (solid) 1.532; valence 1, 2, 3, 4. See Table at element.

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[From Latin rbidus, red; see reudh- in Indo-European roots.]

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rubidium [ruːˈbɪdɪəm]

n

(Chemistry / Elements & Compounds) a soft highly reactive radioactive element of the alkali metal group; the 16th most abundant element in the earth's crust (310 parts per million), occurring principally in pollucite, carnallite, and lepidolite. It is used in electronic valves, photocells, and special glass. Symbol: Rb; atomic no.: 37; atomic wt.: 85.4678; half-life of ⁸⁷Rb: 5 ✕ 10¹¹ years; valency: 1, 2, 3, or 4; relative density: 1.532 (solid), 1.475 (liquid); melting pt.: 39.48°C; boiling pt.: 688°C

[from New Latin, from Latin rubidus dark red, with reference to the two red lines in its spectrum]

rubidic  adj

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rubidium  (r-bd-m)

Symbol Rb

A soft, silvery-white metallic element of the alkali group. It ignites spontaneously in air and reacts violently with water. Rubidium is used in photoelectric cells, in making vacuum tubes, and in radiometric dating. Atomic number 37; atomic weight 85.47; melting point 38.89°C; boiling point 688°C; specific gravity (solid) 1.532; valence 1, 2, 3, 4. See Periodic Table.

Thesaurus

Noun

1.

rubidium - a soft silvery metallic element of the alkali metal group; burns in air and reacts violently in water; occurs in carnallite and lepidolite and pollucite atomic number 37, Rb metal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. carnallite - a white or reddish mineral consisting of hydrous chlorides of potassium and magnesium; used as a fertilizer and as a source of potassium and magnesium lepidolite - a mineral of the mica group; an important source of lithium pollucite - a rare mineral that is an important source of cesium

Translations

rubidium [ruːˈbɪdɪəm] N → rubidio m

rubidium

n (Chem) → Rubidium nt