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Be

Beryllium

Atomic number: 4Mass: 9.0122 uCategory: Alkaline Earth Metal

About Beryllium

Beryllium is a steel-grey, hard, lightweight alkaline earth metal. It is relatively rare in the universe and in the Earth's crust. Beryllium is non-magnetic and has excellent thermal conductivity.

Properties

Period
2
Group
2
Block
S
Category
Alkaline Earth Metal
Electronegativity
1.57 (Pauling)
Ionization Energy
899.5 kJ/mol
Melting Point
1560 K (1287°C)
Boiling Point
2742 K (2469°C)
Density
1.85 g/cm³
Oxidation States
+2

Electron Configuration

1s² 2s²
[He] 2s²
Shell 1:2e⁻
Shell 2:2e⁻

Real-World Uses

Aerospace components
X-ray windows
Nuclear reactors
Gyroscopes
Electronic components

Fun Fact

Beryllium is used in the James Webb Space Telescope's mirrors because it's stiff, light, and doesn't warp at extreme cold temperatures.