Jun 18 2012
Chemical Formula
Rb
Topics Covered
BackgroundBasic
Information OccurrenceIsotopesProduction of RubidiumHealth AspectsKey PropertiesApplications
Background
Robert Bunsen and Gustav Kirchhoff discovered the element Rubidium in 1861
with the help of a spectroscope while analyzing a mineral called lepidolite.
When the mineral was heated, Bunsen and Kirchhoff found deep red spectral lines
from which the rubidium metal was isolated. The name, rubidium was derived from
the word rubidus, which means the deepest red.
Basic Information
| Name |
Rubidium |
| Symbol |
Rb |
| Atomic number |
37 |
| Atomic weight |
85.4678 (3) amu |
| Standard state |
solid at 298 K |
| CAS Registry ID |
7440-17-7 |
| Group in periodic table |
1 |
| Group name |
Alkali metal |
| Period in periodic table |
5 |
| Block in periodic table |
s-block |
| Color |
silvery white |
| Classification |
Metallic |
| Melting Point |
312.46 K (39.31°C or 102.76°F) |
| Boiling Point |
961 K (688°C or 1270°F) |
| Density |
1.53 grams/cm3 |
| Phase at Room Temperature |
Solid |
|
|
Occurrence
Significant amounts of rubidium are present in the minerals such as Lepidolite,
Pollucite and Carnallite. Traces of rubidium are also present in the minerals
such as Leucite and Zinnwaldite. The metal is also found in mineral springs and
seawater. Rubidium is an abundant element at around 35 to 75 ppm.
Isotopes
Rubidium has two naturally occurring isotopes Rubidium-85 and Rubidium-87. Rubidium-87 is a radioactive isotope is used to determine the age of old
rocks. It has a half-life of 49 billion years. It is also used as a
frequency standard in high-accuracy timing equipment such as GPS receivers. It
is also used to produce Bose-Einstein condensates and in laser
cooling.
Production of Rubidium
Rubidium is generally produced as a by-product of lithium refining from Lepidolite. In such cases, rubidium chloride is reduced using saodium or calcium.
Health Aspects
Certain health effects of rubidium are listed below:
- It is moderately toxic by ingestion
- If itt ignites, it will cause thermal burns
- Overexposurecan result in skin and eye burns
- Failure to gain weight, hyper irritation, ataxia, skin ulcers and
nervousness may occur due to over exposure
Key Properties
The key properties of rubidium are:
- It is the second most electropositive metal
- It is soft and silvery
- It is highly inflammable
- It is mildly radioactive
- It ignites spontaneously in air
- It vigorously reacts with water and combines with the halogens
Applications
The applications of rubidium are listed below:
- Rubidium is mainly used to make atomic clocks. These clocks are used only when high-precision time keeping is
required.
- Rubidium is also used in the manufacture of photocells. A photocell
converts light energy to electrical energy.
- Rubidium is ideal for monitoring ischemia, a condition where blood flow is
obstructed through the main coronary arteries.
Source: AZoM.com