Page 13 - Curriculum Visions Dynamic Book

Rn see Radon, Ru see Ruthenium Rubidium (Rb)
Element 37.A member of group 1 (the alkali metals) in the Periodic Table.
Rubidium is a very soft silvery metal that is the second most reactive metal element. Rubidium has to
be kept in dry mineral oil or in an atmosphere of hydrogen because it reacts spontaneously in air and water. When it reacts with water, it releases hydrogen gas, which then catches fire.When put in a flame, it turns
the flame yellowish-violet.
Rubidium forms amalgams with mercury and alloys with gold, cesium, sodium and potassium. Rubidium is solid at normal room temperatures, but it can become liquid on a very hot day because its melting point is below 40°C.
Rubidium is a rare element.
Discovery
It was discovered in Germany in 1861 by Robert Bunsen and Gustav Kirchhoff.
Technology
It has a limited range of uses,
but does go into photocells and special glass.The age of the solar system (4.6 billion years) has been estimated using the decay of a radioactive isotope of rubidium in a stony meteorite.
Geology
It is too reactive to occur as a native element, but appears in minerals that contain potassium, such as biotite and feldspar.
Biology
Rubidium is not found in living things.
Key facts...
Name: rubidium
Symbol: Rb
Atomic number: 37
Atomic weight: 85.47
Position in Periodic Table: group 1 (1)
(alkali metal); period 5
State at room temperature: solid Colour: silvery
Density of solid: 1.53 g/cc
Melting point: 38.9°C
Boiling point: 688°C
Origin of name: from the Latin word
rubidius, meaning dark red after the dark red lines that it produces when looked at through a piece of chemical equipment called a spectrometer
Shell pattern of electrons: 2–8–18–8–1
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