Beryllium Facts

Beryllium is the fourth element of the periodic table. These beryllium facts contain chemical and physical data along with general information and history.

Element cell for Beryllium

Beryllium periodic table tile.

Basic Beryllium Facts

Name: Beryllium

Atomic Number: 4

Element Symbol: Be

Group: 2

Period: 2

Block: s

Element Family: Alkaline Earth

Atomic Mass: 9.012182(3)

Electron Configuration: [He]2s(shorthand) or 1s22s2 (full)

Discovery: Louis-Nicholas Vauquelin in 1798.
Vauquelin was investigating the chemical properties of beryls. Beryls come in a wide variety of colors, but seem to have similar chemical attributes. He isolated a compound containing an unknown element with a sweet taste. Pure beryllium was first isolated in 1828 by German chemist Friederich Wöhler and French chemist Antoine Bussy independently from each other.

Name Origin: Vauquelin named his element after the substance he was investigating, beryl. He first named the substance Earth of beryl, but switched to glucenum to reflect the sweet taste. Wöhler proposed changing the name from the taste property since there are many elements with a sweet taste. He named the element beryllium after the Greek word beryllos for beryl.

Natural Isotopes:

Beryllium is nearly 100% beryllium-9. Two other isotopes can be found in trace amounts.

Beryllium-7 is a radioactive isotope containing 3 neutrons. It decays into 7Li through electron capture. Its half-life is 53.12 days.

Beryllium-9 is the most common natural isotope. It contains 5 neutrons and is stable.

Beryllium-10 is a radioactive isotope containing 6 neutrons. It decays into 10B by β- decay with a half-life 1.36 million years.

Beryllium Crystal

Large crystal of pure beryllium. Credit: Heinrich Pniok/Creative Commons

Physical Data

Density: 1.85 g/cm3

Melting Point: 1560 K (1287 ºC or 2349 ºF)

Boiling Point: 3243 K (2970 ºC or 5338 ºF)

State at 20ºC: Solid

Heat of Fusion: 12.2 kJ/mol

Heat of Vaporization: 292 kJ/mol

Molar Heat Capacity: 16.443 J/mol·K

Beryllium Atom

Electron configuration of a beryllium atom.

Atomic Data

Atomic Radius: 1.12 Å (empirical)

Covalent Radius: 0.96 Å

Van der Waals Radius:  1.82 Å

Electron Affinity: not stable

Electronegativity: (Pauling scale): 1.85

1st Ionization Energy: 899.504 kJ/mol

2nd Ionization Energy: 1757.108 kJ/mol

3rd Ionization Energy: 14848.767 kJ/mol

4th Ionization Energy: 21006.658 kJ/mol

Common Oxidation States: +2 (common), +1 (uncommon)


Morganite, aquamarine and heliodor. These three minerals are all beryls. Credit: Chris Ralph/Public Domain

Fun Beryllium Facts

  • Beryllium is a soft, silvery-white metal with low density. Crystals are strong but brittle.
  • Beryllium is added to alloys to increase electrical and thermal conductivity.
  • Beryllium tools are made to prevent sparking when the tool strikes another metal. These tools are vital in environments where the risk of flames or explosions are high.
  • Beryllium has the highest melting point of the light metals.
  • Beryllium was discovered while investigating beryls. Beryls are minerals with chemical formula Be3Al2(SiO3)6 that come in many different colors.
  • Beryllium was found to have a sweet taste. One standard test for early chemists was a taste test. What does the sample taste like? Today, we know beryllium and its compounds are all extremely toxic and carcinogenic.
  • One early name for beryllium was glyceynum after the Greek word glykis meaning sweet.
  • Beryllium is relatively transparent to x-rays. Beryllium foil is used as the window for x-ray emitters.
  • Beryllium is used in nuclear as neutron moderators and reflectors.
  • Beryllium is used as a target for neutron production. When bombarded with alpha particles (helium nuclei), the resulting reaction can produce a high yield of neutrons.

Learn more about elements on the periodic table.

Beryllium Facts
Last modified: May 20th, 2015 by Todd Helmenstine
This entry was posted in Elements on by .

About Todd Helmenstine

Todd Helmenstine is the physicist/mathematician who creates most of the images and PDF files found on Nearly all of the graphics are created in Adobe Illustrator, Fireworks and Photoshop. Todd also writes many of the example problems and general news articles found on the site.