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Beryllium

chemical element with symbol Be and atomic number 4
(Redirected from Element 4)

Beryllium is in group 2 of the periodic table, so it is an alkaline earth metal. It is grayish (slightly gray) in color. It has an atomic number of 4 and is symbolized by the letters Be. It is toxic and should not be handled without proper training.

Beryllium, 00Be
Beryllium
Pronunciation/bəˈrɪliəm/ ​(bə-RIL-ee-əm)
Appearancewhite-gray metallic
Standard atomic weight Ar°(Be)
9.0121831(5)[1]
Beryllium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
–
↑
Be
↓
Mg
lithium ← beryllium → boron
Groupgroup 2 (alkaline earth metals)
Periodperiod 2
Block  s-block
Electron configuration[He] 2s2
Electrons per shell2, 2
Physical properties
Phase at STPsolid
Melting point1560 K ​(1287 °C, ​2349 °F)
Boiling point2742 K ​(2469 °C, ​4476 °F)
Density (near r.t.)1.85 g/cm3
when liquid (at m.p.)1.690 g/cm3
Critical point5205 K,  MPa (extrapolated)
Heat of fusion12.2 kJ/mol
Heat of vaporization292 kJ/mol
Molar heat capacity16.443 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1462 1608 1791 2023 2327 2742
Atomic properties
Oxidation states0,[2] +1,[3] +2 (an amphoteric oxide)
ElectronegativityPauling scale: 1.57
Ionization energies
  • 1st: 899.5 kJ/mol
  • 2nd: 1757.1 kJ/mol
  • 3rd: 14,848.7 kJ/mol
  • (more)
Atomic radiusempirical: 112 pm
Covalent radius96±3 pm
Van der Waals radius153 pm
Color lines in a spectral range
Spectral lines of beryllium
Other properties
Natural occurrenceprimordial
Crystal structure ​hexagonal close-packed (hcp)
Hexagonal close packed crystal structure for beryllium
Speed of sound thin rod12,890 m/s (at r.t.)[4]
Thermal expansion11.3 µm/(m⋅K) (at 25 °C)
Thermal conductivity200 W/(m⋅K)
Electrical resistivity36 nΩ⋅m (at 20 °C)
Magnetic orderingdiamagnetic
Molar magnetic susceptibility−9.0·10−6 cm3/mol[5]
Young's modulus287 GPa
Shear modulus132 GPa
Bulk modulus130 GPa
Poisson ratio0.032
Mohs hardness5.5
Vickers hardness1670 MPa
Brinell hardness590–1320 MPa
CAS Number7440-41-7
History
DiscoveryLouis Nicolas Vauquelin (1798)
First isolationFriedrich Wöhler & Antoine Bussy (1828)
Isotopes of beryllium
Main isotopes[6] Decay
abun­dance half-life (t1/2) mode pro­duct
7Be trace 53.22 d ε 7Li
8Be 0% (extinct) 81.9 as α 4He
9Be 100% stable
10Be trace 1.387×106 y β− 10B
 Category: Beryllium
| references

Beryllium has 4 electrons, 4 protons, and 5 neutrons.

Beryllium has one of the highest melting points of the light metals: 1560 K (1287 °C). It is added to other metals to make stronger alloys. Beryllium-copper alloy is used in tools because it does not make sparks.

At standard temperature and pressure, beryllium resists oxidation when exposed to oxygen.

Beryllium is best known for the chemical compounds it forms. Beryllium combines with aluminium, silicon and oxygen to make a mineral called beryl. Emerald and aquamarine are two varieties of beryl which are used as gemstones in jewelry.

Since it has a very high stiffness to weight ratio, beryllium is used to make the diaphragms in some high-end speakers.

Uses

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Beryllium is used to make jet aircrafts, guided missiles, spacecraft, and satellites, including the James Webb telescope.[8][9] Beryllium can reflect neutrons, and thin foils of beryllium are sometimes used in nuclear weapons as the outer layer of the plutonium pits.[10] Beryllium is also used in fuel rods for CANDU reactors. Beryllium is used to make many dental alloys.[8][9]

Rarity

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It is a relatively rare element in the universe. It usually occurs when larger atomic nuclei have split up. In stars, beryllium is depleted because it is fused and builds larger elements.

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References

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  1. ↑ "Standard Atomic Weights: Beryllium". CIAAW. 2013.
  2. ↑ Be(0) has been observed; see "Beryllium(0) Complex Found". Chemistry Europe. 13 June 2016.
  3. ↑ "Beryllium: Beryllium(I) Hydride compound data" (PDF). bernath.uwaterloo.ca. Retrieved 2007-12-10.
  4. ↑ Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, FL: CRC Press. p. 14.48. ISBN 1439855110.
  5. ↑ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
  6. ↑ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  7. ↑ "Beryllium: Beryllium(I) Hydride compound data" (PDF). bernath.uwaterloo.ca. Retrieved 2007-12-10.
  8. ↑ 8.0 8.1 Metals handbook. Davis, J. R. (Joseph R.), ASM International. Handbook Committee. (Desk ed., 2nd ed.). Materials Park, Oh.: ASM International. 1998. ISBN 0-87170-654-7. OCLC 40452949.{{cite book}}: CS1 maint: others (link)
  9. ↑ 9.0 9.1 Schwartz, Mel M. (2002). Encyclopedia of materials, parts, and finishes (2nd ed.). Boca Raton: CRC Press. ISBN 1-56676-661-3. OCLC 48907078.
  10. ↑ Barnaby, Frank. (1993). How nuclear weapons spread : nuclear-weapon proliferation in the 1990s. London: Routledge. ISBN 0-203-16832-1. OCLC 252789074.



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