Beryllium
Definition and meaning of Beryllium in chemistry.
![Beryllium element card: symbol Be, atomic number 4, atomic mass 9.0122, electron configuration [He] 2s², oxidation states +2, Alkaline earth metal, group 2, period 2, solid at room temperature.](/assets/images/terms/beryllium-chemical-element.webp)
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a very light and rigid metal with a +2 charge. This rare element forms when larger atomic nuclei break apart in space.
In more detail
Beryllium sits at the top of group 2 on the periodic table. It is a steel-gray alkaline earth metal that is strong, lightweight, and brittle. For a light metal, beryllium has an exceptionally high melting point.
It also conducts heat very well, making it useful in hot environments. Chemically, beryllium resists breaking down at normal room temperatures. It quickly forms a thin layer of beryllium oxide on its surface.
This tough oxide layer stops water or oxygen from reacting any further. On Earth, you will mostly find beryllium in silicate minerals like beryl. Emerald and aquamarine are famous, highly valued gemstone forms of beryl.
Beryllium has a unique and important reaction to alpha particles. An alpha particle is a fast-moving helium nucleus that acts as radiation. When struck by alpha particles, a beryllium atom releases uncharged neutrons.
This specific behavior actually led scientists to discover the neutron. This ability also makes beryllium very important for running nuclear reactors. Finally, beryllium has an excellent stiffness-to-weight ratio compared to other metals. Engineers highly value this rare trait for specialized structural parts in machines.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Be |
| Atomic number | 4 |
| Atomic mass | 9.0122 u |
| Category | Alkaline-Earth-Metal |
| Melting point | 1287 °C (2349 °F) |
| Discovery year | 1798 |
One major use is mixing beryllium with copper to make an alloy. An alloy is a solid mixture of two or more metallic elements. Beryllium copper is a very strong, versatile, and useful material. Tools made from this alloy do not create sparks when dropped. This is crucial for worker safety in highly explosive environments. Aerospace engineers use beryllium copper to build precise airplane components. Telecommunications companies also use it for highly reliable electrical contacts.
Frequently asked questions
Is beryllium hazardous to human health?
Yes, inhaling beryllium dust can cause a severe lung disease called berylliosis. Doctors also classify the element as a known human carcinogen.
How do scientists use beryllium in nuclear reactors?
Beryllium acts as a neutron reflector and moderator. It slows down fast neutrons and bounces them back into the core to maintain the nuclear chain reaction.
Related terms
Sources & references
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