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|
| Appearance
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white-gray metallic
150px
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| General properties
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| Name, symbol, number
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beryllium, Be, 4
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| Pronunciation
|
/bəˈrɪliəm/ bə-RIL-ee-əm
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| Element category
|
alkaline earth metal
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| Group, period, block
|
2, 2, s
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| Standard atomic weight
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9.012182(3) g·mol−1
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| Electron configuration
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1s2 2s2
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| Electrons per shell
|
2, 2 (Image)
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| Physical properties
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| Phase
|
solid
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| Density (near r.t.)
|
1.85 g·cm−3
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| Liquid density at m.p.
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1.690 g·cm−3
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| Melting point
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1560 K, 1287 °C, 2349 °F
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| Boiling point
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2742 K, 2469 °C, 4476 °F
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| Heat of fusion
|
12.2 kJ·mol−1
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| Heat of vaporization
|
297 kJ·mol−1
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| Specific heat capacity
|
(25 °C) 16.443 J·mol−1·K−1
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| Vapor pressure
|
| P (Pa)
|
1
|
10
|
100
|
1 k
|
10 k
|
100 k
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| at T (K)
|
1462
|
1608
|
1791
|
2023
|
2327
|
2742
|
|
| Atomic properties
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| Oxidation states
|
2, 1[1]
(amphoteric oxide)
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| Electronegativity
|
1.57 (Pauling scale)
|
Ionization energies
(more)
|
1st: 899.5 kJ·mol−1
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| 2nd: 1757.1 kJ·mol−1
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| 3rd: 14848.7 kJ·mol−1
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| Atomic radius
|
105[2] pm
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| Atomic radius (calc.)
|
112 [3] pm
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| Covalent radius
|
96±3 pm
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| Van der Waals radius
|
153 pm
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| Miscellanea
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| Crystal structure
|
hexagonal
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| Magnetic ordering
|
diamagnetic
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| Electrical resistivity
|
(20 °C) 36 nΩ·m
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| Thermal conductivity
|
(300 K) 200 W·m−1·K−1
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| Thermal expansion
|
(25 °C) 11.3 µm·m−1·K−1
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| Speed of sound (thin rod)
|
(r.t.) 12870[4] m·s−1
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| Young's modulus
|
287 GPa
|
| Shear modulus
|
132 GPa
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| Bulk modulus
|
130 GPa
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| Poisson ratio
|
0.032
|
| Mohs hardness
|
5.5
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| Vickers hardness
|
1670 MPa
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| Brinell hardness
|
600 MPa
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| CAS registry number
|
7440-41-7
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| Most stable isotopes
|
| Main article: Isotopes of beryllium
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