• Discovered in 1861
  • Atomic number is 37
  • Atomic mass is 85.4678
  • Melting point is 103.1 F'
  • Solid at room temperature
  • Classified as a metal
  • Period number 5
  • Group number 1
  • Group name: Alkali Metals
  • 1 Valence electron
  • Used in the manufacture of photocells and special glasses
  • Used in fireworks, satellites, and atomic clocks


  • R- Rubidus means "deep red"
  • U- Used for Photocells
  • B- Breaks easily
  • I- Is useful in film batteries
  • D- Dense
  • I- Is solid at room temperature
  • U- Utilized in atomic clocks
  • M- Makes a purple color in fireworks


Found in 1861 by Robert Bunsen and Gustav Kirchhoff, in Heidelberg, Germany, In the mineral lepidolite through the use of spectroscope. Rubidium is a soft, silvery-white metallic element of the alkali metal group. Rubidium is highly reactive with properties similar to those of other alkali metals, such as rapid oxidation in air. Rubidium is easily vaporized and has a convenient spectral absorption range.


Common rubidium compounds: Rubidium Chloride (RbCl), rubidium monoxide (Rb20) and rubidium copper sulfate (Rb2SO). A compound of rubidium, silver and iodine, RbAg4I5, has interesting electrical characteristic and might be useful in thin film batteries


Rubidium Oxide- RbO2

Rb+O2= RbO2



Rubidium % comp: 72%

Oxygen % comp: 27%


  • They have low melting and boiling points compared to most other metals
  • Very soft and can be cut easily with a knife
  • Very low densities
  • React quickly with water producing hydroxides and hydrogen gas.
  • Their hydroxides and oxides dissolve in water to form alkaline solutions
Big image
Alkali Metals - 19 Reactions of rubidium and caesium with the air