Rubidium
Simplified 2D Bohr model:Central red circle is the nucleus (proton). Blue ring represents the electron's orbit. Small blue dot is the electron. Note: This basic model doesn't show quantum behavior.
CLASSIFICATION:
Alkali Metal
Belonging to the alkali metal group, rubidium shares their characteristic high reactivity, particularly with water. This necessitates storage under oil or in a vacuum to prevent violent reactions.
85.4678 u
Appearance: Silvery-white, soft metal
Rubidium, a member of the alkali metal family, stands out with its silvery-white metallic luster and remarkable softness. Sharing traits with its alkali brethren like potassium, rubidium exhibits high reactivity, igniting spontaneously upon contact with air. Its unique properties make it a valuable element in various scientific and technological applications.
37
37
48
eV
4. Discovery and History
39.3 °C
688 °C
1.532 g/cm³
248 pm
55.9 cm³/mol
211 pm
31.06 J/(mol·K)
58.2 W/(m·K)
1300 m/s (in metallic state)
1.532 g/cm³
0.3
58.2 W/(m·K)
0.216 MPa
364 J/(kg·K) at 25 °C
90 µm/(m·K)
Melts at 39.3 °C and boils at 688 °C under standard atmospheric pressure
Rubidium's high reactivity is a defining characteristic. It reacts vigorously with water, producing rubidium hydroxide and hydrogen gas, and readily oxidizes in air, forming rubidium oxide.
+1
-2.92 V
Rubidium's chemistry is dominated by its eagerness to lose its single valence electron, leading to the formation of ionic compounds where it exists in the +1 oxidation state.
Paramagnetic - weakly attracted by a magnet
12.5 nΩ·m at 20 °C
Not typically specified for Rubidium
Not applicable for metals in the solid state
Reflects 75% of incident light in the visible spectrum
Rubidium exhibits characteristic absorption lines in the visible and near-infrared regions, which are crucial for its identification and analysis through techniques like atomic absorption spectroscopy.
n=5, indicating its period in the periodic table and the energy level of its valence electron. (l=0 for the s orbital, signifying a spherical electron cloud with no angular momentum.)
Total Electrons: 37, Shells: 2, 8, 18, 8, 1
The energy levels of rubidium are complex and influenced by factors such as electron-electron interactions and spin-orbit coupling. Spectroscopic techniques are used to study these energy levels and their transitions.
[Kr] 5s1
Rubidium's electron configuration reveals its single valence electron in the outermost 5s orbital, responsible for its characteristic +1 oxidation state and high reactivity as it readily loses this electron to achieve a stable noble gas configuration.
Earth's Crust
Rubidium is found in trace amounts in the Earth's crust, primarily within minerals like lepidolite, pollucite, and carnallite. Its high reactivity prevents it from existing in its pure, elemental form in nature.
Body-Centered Cubic (BCC)
Temperature: Above 39.3 °C
In its solid state, rubidium adopts a body-centered cubic crystal structure, where each atom is surrounded by eight neighboring atoms at the corners of a cube and one atom in the center.
+1
Rubidium exhibits a strong preference for the +1 oxidation state in its compounds due to the ease with which it loses its single valence electron.
Rubidium Chloride (RbCl)
RbCl
A colorless crystalline salt, widely used in biochemistry and molecular biology for applications such as DNA isolation and protein purification.
Rubidium Hydroxide (RbOH)
RbOH
A strong base with properties similar to potassium hydroxide, used in research and certain industrial processes.
Rubidium Carbonate (Rb2CO3)
Rb2CO3
A white, water-soluble salt used in the production of special glasses and as a catalyst in some organic reactions.
Rubidium Nitrate (RbNO3)
RbNO3
Used in pyrotechnics and as a source of rubidium in other chemical syntheses.
780.0 nm nm
Strong
Characteristic red color in atomic spectroscopy, crucial for identification and analysis of rubidium.
420.2 nm nm
Medium
Violet line, also significant in rubidium's spectral signature.
17. Practical Applications
Atomic Clocks
The rubidium-87 isotope, with its precise transition frequency, is crucial in atomic clocks, providing exceptional accuracy in timekeeping.
Biomedical Research
Rubidium compounds, especially rubidium chloride, are used in biomedical research, including DNA research, cell studies, and pharmaceutical development.
Electronics
Rubidium finds applications in photocells, vacuum tubes, and certain types of semiconductors due to its unique electronic properties.
Geochemistry and Dating
The radioactive decay of rubidium-87 to strontium-87 is utilized in rubidium-strontium dating, a method for determining the age of rocks and minerals.
26. Synthesis and Production
Not synthesized due to its natural abundance; extracted from minerals like lepidolite.
Rubidium is typically extracted from mineral ores through processes like flotation, electrolysis, and fractional distillation.
Global production of rubidium is relatively limited compared to other elements, primarily due to its specialized applications.
20. Economic Data
Market Price: Variable, influenced by factors such as purity, demand, and global supply
Producing Countries: Canada, Russia, and some European countries are among the primary sources of rubidium production.
Industrial Use: Primarily used in research and development, with specialized applications in atomic clocks, electronics, and medicine.
Description: The economic significance of rubidium lies in its niche applications rather than large-scale industrial use.
18. Biological Role
Not essential in human biology
Rubidium has no known essential biological function in humans. While it can be absorbed similarly to potassium, it does not appear to play a significant role in biochemical processes.
Subject to regulations regarding transportation, storage, and handling due to its reactive nature and potential hazards.
Regulations vary by country and region, but generally focus on ensuring safe handling, storage, and disposal of rubidium and its compounds to protect human health and the environment.
19. Health and Environmental Impact
Rubidium's main health risks stem from its high reactivity, which can lead to burns and explosions upon contact with water or air. Safe handling practices are crucial to mitigate these risks.
Due to its low abundance and the controlled nature of its applications, rubidium's environmental impact is considered minimal. Responsible extraction and disposal practices are essential to maintain environmental safety.
27. Environmental Safety
Rubidium's high reactivity poses risks of fire and explosion when it comes into contact with water or air. Proper handling with protective equipment and adherence to safety protocols are essential to prevent accidents.
Rubidium must be stored in inert environments, away from moisture and air, to prevent hazardous reactions. Safety data sheets and training are crucial for anyone handling this element.
Handling: Rubidium should be handled with extreme care in inert atmospheres (e.g., argon or nitrogen) to prevent contact with air or moisture, which can lead to spontaneous combustion.
Storage: Stored under oil or in vacuum-sealed ampoules to prevent exposure to air and moisture.
First Aid Measures: In case of exposure, immediate medical attention is required. Water should not be used on rubidium fires as it can exacerbate the reaction. Specialized fire extinguishers are necessary.
23. Future Predictions
Advanced Technology Applications
Rubidium's unique properties may lead to increased use in emerging technologies such as quantum computing, advanced energy storage systems, and specialized electronics.
Medical Research and Development
Further research may uncover potential medical applications for rubidium compounds in areas such as diagnostics and therapeutics.