Beryllium

Figure 1. Beryllium, with atomic number 4 and atomic weight of 9.012.

Beryllium is the 4^th element on the periodic table of elements, and is an alkaline earth element. Some of its properties are listed below:

Atomic weight	9.012
Density (at 0oC)	1.85 g/cm3
Boiling point	2741 K
Melting point	1560 K

Beryllium is an alkaline earth metal. It has low density and is silver-white in colour. It is found in multiple minerals, including beryl which has precious forms as emerald and aquamarine.

Beryllium Uses

Figure 2. Beryllium foil X-ray window.

Beryllium is usually alloyed with copper or nickel to increase their thermal and electrical conductivity. These alloys are used to make items like gyroscopes, springs, electrical contacts, spot-welding electrodes, and non-sparking tools. Other alloys are used for aircraft, spacecraft, and satellites. Beryllium alloys tend to be stiff, lightweight, and stable over a wide range of temperatures (due to its high melting point), making them ideal for aerial equipment.

Beryllium foil is sometimes used in X-ray lithography. The foil is used as a "window" for the X-rays to take clear images of the item being inspected (Figure 2).

Beryllium's high melting point makes it useful in nuclear reactors and other nuclear work. Beryllium can reflect neutrons (neutron reflector), which lets nuclear reactors have a more even distribution of neutrons.

Isotopes

Beryllium has one isotope found in nature:

Symbol	Natural Abundance
9Be	100%

Video

The video below is from the University of Nottingham's periodic videos project. They have created a complete suite of short videos on every element on the periodic table of elements.

For Further Reading

• Periodic table of elements
• Metal
• Greenhouse effect
• Pollution
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