Quick Facts
| Property | Value |
|---|---|
| Symbol | Be |
| Atomic Number | 4 |
| Atomic Mass | 9.0122 u |
| Category | Alkaline Earth Metal |
| Period | 2 |
| Group | 2 |
| Block | s |
| Electron Configuration | [He] 2s² |
Physical Properties
| Property | Value |
|---|---|
| State at 20°C | Solid |
| Density | 1.85 g/cm³ |
| Melting Point | 1287°C (1560 K) |
| Boiling Point | 2469°C (2742 K) |
| Appearance | Steel-gray, strong, lightweight metal |
Atomic Properties
| Property | Value |
|---|---|
| Electron Configuration | [He] 2s² |
| Electronegativity | 1.57 (Pauling scale) |
| First Ionization Energy | 899.5 kJ/mol |
| Atomic Radius | 112 pm |
| Covalent Radius | 96 pm |
| Van der Waals Radius | 153 pm |
History and Discovery
Discovered by: Louis Nicolas Vauquelin Year of Discovery: 1798 Location: Paris, France
Etymology
The name "beryllium" comes from the Greek word "beryllos" for the mineral beryl, from which it was first isolated. Beryl itself was named after the precious gemstone. The element was initially called "glucinium" (from Greek "glykys" meaning sweet) due to the sweet taste of its compounds.
Discovery Story
Louis Nicolas Vauquelin discovered beryllium in 1798 when analyzing beryl and emerald gemstones. He found they contained a new element, though he could not isolate it. In 1828, Friedrich Wöhler in Germany and Antoine Bussy in France independently isolated beryllium metal by reducing beryllium chloride with potassium.
Isotopes
| Isotope | Natural Abundance | Half-life | Decay Mode |
|---|---|---|---|
| ⁹Be | 100% | Stable | - |
| ⁷Be | Trace (cosmogenic) | 53.22 days | Electron capture |
| ¹⁰Be | Trace (cosmogenic) | 1.39 million years | β⁻ |
Occurrence
Natural Abundance
Beryllium is relatively rare, comprising about 2-6 ppm of the Earth's crust. It is found in about 100 mineral species, with the most important being beryl (Be₃Al₂Si₆O₁₈) and bertrandite (Be₄Si₂O₇(OH)₂). Significant deposits exist in the United States, China, Mozambique, and Brazil.
Extraction and Production
- From Bertrandite: Primary source in the US—ore is processed with sulfuric acid
- From Beryl: Ore is melted and treated to extract beryllium hydroxide
- Refining: Beryllium hydroxide is converted to fluoride, then reduced with magnesium
Applications and Uses
Industrial Applications
- Aerospace components (low density, high stiffness)
- Beryllium-copper alloys (springs, electrical connectors)
- Nuclear reactor moderators and reflectors
- High-speed computer components
Scientific Applications
- X-ray windows (transparent to X-rays)
- Particle physics detectors
- Neutron sources (when bombarded with alpha particles)
- Gyroscopes and precision instruments
Technological Applications
- Satellite and spacecraft structural components
- Defense and military applications
- Telecommunications equipment
- Semiconductors and electronics
Other Uses
- Golf club heads
- High-end audio speakers (tweeter domes)
- Medical and dental equipment
Biological Role
Beryllium has no known biological role and is highly toxic to humans.
In the Human Body
Beryllium is not normally found in the human body and has no beneficial function.
Health Effects
Chronic exposure can cause berylliosis, a serious lung disease. It is also a known carcinogen.
Safety and Hazards
Toxicity
Beryllium and its compounds are highly toxic. Inhalation of beryllium particles can cause acute beryllium disease or chronic berylliosis, an irreversible lung condition. Beryllium is classified as a Group 1 carcinogen (carcinogenic to humans).
Handling Precautions
- Strict exposure controls required in industrial settings
- Use respiratory protection and engineering controls
- Avoid dust generation
- Machining must be done with proper containment and ventilation
- Regular medical monitoring for exposed workers
- US OSHA permissible exposure limit: 0.2 μg/m³
Environmental Impact
Beryllium contamination can occur near mining and processing facilities. It does not bioaccumulate significantly but can persist in soil and sediments.
Interesting Facts
- Beryllium is one of the lightest metals, about one-third the weight of aluminum
- It has a very high melting point for such a light metal
- Beryllium is transparent to X-rays, making it ideal for X-ray machine windows
- The gems emerald and aquamarine are both forms of beryl containing beryllium
- Despite its toxicity, beryllium compounds were once used to coat fluorescent lamp tubes