19 Rubidium Uses: Facts You Should Know!

Rubidium is a chemical element having an atomic number of 37 and a molar mass of 85.468 g/mol. Let us have a look at the uses of rubidium (Rb).

Rubidium, a rare and expensive metal, is generally used in different industries like-

• Research field
• Glass industry
• Space exploration
• Agricultural industry

Let us focus on the application of different rubidium compounds like oxide, chloride, hydroxide, iodides, etc in detail in this article.

Research Field

The uses of rubidium in electronics industry are written below-

• Thermoelectric generator which uses magnetohydrodynamic principle.
• Laser cooling and Bose-Einstein condensation.
• Atomic clocks which use hyperfine structure.
• GPS to produce a ‘primary frequency’.

Glass Industry

The applications of rubidium in glassmaking industry are listed below-

• Manufacturing of special types of glasses.
• Vacuum tubes as a getter, a material which can combine with and removes trace gases from vacuum tubes.
• Glasses and ceramics and in fireworks to give them a purple color.

Space Exploration

Rubidium is widely used in space related research and spacecrafts like-

• As a propellent in ion engines on spacecraft.
• Ion engines, vapor turbines and getter in vacuum tubes.

Agricultural Industry

The uses of rubidium in agricultural industries are not completely discovered. But it plays an important role in the growth of plants like below because it belongs to ultra-trace elements which are essential for plants and animals.

Rubidium Iodide Uses

Rubidium iodide (RbI) is a salt of Rb (molar mass 212.3723 g/mol) formed by the reaction between Rb and I₂.

The industries that use RbI, are discussed below.

• Laboratory
• Glassmaking
• Electronics

Laboratory

Manufacturing metal rubidium and other different rubidium salts in laboratories.

Glassmaking

To producte of special glass.

Electronics

To produce of high-energy batteries, and crystal scintillation counters.

Rubidium Oxide Uses

Rubidium oxide (Rb₂O) is a highly reactive toward H₂O. It acts as a strong base and forms RbOH through an exothermic reaction. Rb₂O is used in mainly power generation field-

• cathode of solid oxide fuel cells as it has some conductivity power.
• Oxygen generation systems.

Rubidium-87 Uses

Rubidium-87 is a stable isotope (abundance – 27.83%) of Rb among its 36 isotopes with a molar mass of 86.9092 g/mol.

The industrial applications of Rb-87 are explored in detail.

• Electronics
• Age determination

Electronics

• As a frequency standard in high-frequency timing types of equipment like GPS receivers.
• To generate Bose-Einstein condensates and also in laser cooling, and optical magnetometers.

Age Determination

• Determination the age of old rocks (t_1/2 = 49 billion years).
• Rubidium-strontium dating method (radiometric dating technique).

Rubidium Chloride Uses

Rubidium chloride is one of the most useful halides of Rb that presents as a white crystalline solid.

Rubidium chloride has a wide range of uses in the following industries like-

• Research Laboratories
• Industry related to biochemistry/ molecular biology

Research Laboratories

• As a gasoline additive to develop its octane number.
• The coupling between circadian oscillators can be modified by RbCl through reduced photaic input to the suprachiasmatic nuclei.
• RbCl is an excellent non-invasive biomarker. It can be dissolved in water and can be accepted by other organisms.

Industry related to biochemistry/ molecular biology

• A cell reacted with a hypotonic solution of RbCl will expand and as a result, the expulsion of membrane proteins permits DNA (negatively charged) for binding.
• Positron Emission Tomography which can perform the imaging of myocardium perfusion in human beings.

Rubidium Hydroxide Uses

Rubidium hydroxide is a highly reactive solid compound with the chemical formula of RbOH. It is also a hygroscopic compound.

The industrial uses of rubidium hydroxide are described in the below points.

• Catalyst industry and research field
• Electronics
• Glass industry

Catalyst industry and research field

• As the catalyst in different chemical reactions. For example, oxidative chlorination catalyst.
• To prevent waste of the expensive element Rb.

Electronics

Photography and electric storage batteries.

Glass Industry

Fireworks instead of metal rubidium to get a violet color.

Conclusion

Rubidium is a soft, ductile, and whitish-grey solid metal with a radioactive nature. It has a density (1.532 g/cm³) higher than water. A total of 5 main isotopic forms of Rb are available on earth (⁸⁵Rb and ⁸⁷Rb are the most stable). It also possesses very low ionization energy with comparing to other alkali metals.