Preparation, Properties And Uses Of Rubidium

Rubidium is a soft whitish grey solid with the symbol (Rb). It is an alkali earth metal with an atomic number of 37 that was found in Heidelberg, Germany in the year 1861 by chemists Robert Bunsen and Gustav Klimt while analyzing samples of the mineral lepidolite with a spectroscope. It is the second most electropositive of the alkali metals. The name “Rubidium” comes from the Latin word “rubidus” which means deep red. It occurs naturally in leucite, pollucite, carnallite and zinnwaldite.


The following are the unique properties of rubidium.

  1. Rubidium is a soft whitish grey solid.
  2. It  is an alkali metal.
  3. It has a density that is higher than water.
  4. It has a melting point of 39.3°C.
  5. It reacts violently when mixed in water.
  6. It ignites spontaneously in the air.
  7. It forms amalgams with mercury and alloy with the following elements; caesium, sodium, iron, potassium and gold.
  8. It is solid at room temperature unlike mercury which is a liquid at room temperature.
  9. It has an ionization of 406 kg/mol.
  10. It can be easily vaporized.
  11. It is a soft and ductile element.
  12. It has an atomic number of 37.
  13. It has an atomic mass of 85.4678 g/mol.
  14. It has an electronegativity of 0.8
  15. It has a density of 1.53g/cm.
  16. It has a boiling point of 696°C.
  17. It has an atomic radius of 0.149.
  18. It has two isotopes which are Rubidium-85 and Rubidium-87.
  19. This is highly flammable element. 
  20. It is the second most electropositive metal on the periodic table.
READ MORE:  Digestion and Enzymatic Actions of Gastric juice and Pepsin in the Stomach


Rubidium is used in the production of many wholesome items like.

  1. The production of fireworks in order to produce  purple color when the firework is lighted.
  2. It is used in laser cooling.
  3. It is used in Bose Einstein condensation.
  4. It is used in the manufacturing of photocells.
  5. It is used in the production of special glasses.
  6. It is used in the removal of residual gases from vacuum tubes.
  7. It is used in producing superoxide by burning oxygen.
  8. It is used in atomic clocks.


Rubidium is generally produced as a by-product of the element, lithium refined from Lepidolite. In this case, rubidium chloride is reduced using sodium or calcium.


This element has a Body Centered Cubic structure and a silver color.

NB: When an element is said to have a body-centered cubic unit cell it means that the said element has atoms at each of the eight corners of a cube plus one atom in the center of the cube.

It has an electronic configuration of 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 4 s 2 3 d 10 4 p 6 5 s 1 and has a valency of 1. The nucleus of this element consists of 37 protons, 48 neutrons and 37 electrons which are all binded to the nucleus, with a single, relatively unstable electron in the outer shell.

READ MORE:  Significance and Properties of the Homologous Series

Harmful Effects of Rubidium

Rubidium is a moderately toxic element that when ingested becomes toxic to the human body thereby causing burns and perforations of the gastrointestinal tract. It reacts with the moisture on the surface of the skin to form another element called rubidium hydroxide which causes chemical burns on the places where the moisture is found.

Interesting Facts About Rubidium

The element rubidium is a very reactive alkali metal found in group 1 and period 5 of the periodic table. It is used in the production of atomic clocks and fireworks. Rubidium, unlike francium, occurs abundantly in nature. It melts a little above the normal body temperature of 37°C and is solid at room temperature and it is less dense than water. It occurs naturally in the minerals pollucite, carnallite, leucite and lepidolite. Its flame produces a red/red-violet color.


What foods contain rubidium?

Rubidium is found in the different types of food we consume, some of these foods containing this element are; garden tomatoes, sweet oranges, black walnuts, and coconut, poultry meat, freshwater fish, coffee and black tea.

READ MORE:  Dalton's Atomic Theory: Postulates, Limitations, Merits & FAQs

How much is a gram of rubidium?

Due to its abundance, a gram of rubidium is sold at $93.40. It is a cheap element that can be sold legally to those in need of it.

Is rubidium explosive in water?

Just like every other alkali metal, rubidium is explosive in water. It reacts violently when mixed in water and produces rubidium hydroxide solution and hydrogen.

Is rubidium radioactive?

Yes, rabidium is a slightly radioactive element which is used to locate brain tumours, as it collects in tumours but not in normal tissue.  

Is rubidium toxic?

When in contact with the skin or any part of a living organism, be it plant or animal, rubidium can be toxic. When ingested it can cause burns in the gastrointestinal tract and when it comes in contact with the skin, it reacts with the moisture on the skin leading to severe burns.

In the order of their reactivity, which is more reactive?

1.Sodium 2.Potassium 3. Rubidium 4.Caesium

In the order of their reactivity these elements are arranged as Caesium, Rubidium, Potassium and Sodium.