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Friday, February 10, 2023

Beryllium

 

Beryllium, 4Be
Be-140g.jpg
Beryllium
Pronunciation/bəˈrɪliəm/ (bə-RIL-ee-əm)
Appearancewhite-gray metallic
Standard atomic weight Ar°(Be)
  • 9.0121831±0.0000005
  • 9.0122±0.0001 (abridged)[1]
Beryllium in the periodic table
HydrogenHelium
LithiumBerylliumBoronCarbonNitrogenOxygenFluorineNeon
SodiumMagnesiumAluminiumSiliconPhosphorusSulfurChlorineArgon
PotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseIronCobaltNickelCopperZincGalliumGermaniumArsenicSeleniumBromineKrypton
RubidiumStrontiumYttriumZirconiumNiobiumMolybdenumTechnetiumRutheniumRhodiumPalladiumSilverCadmiumIndiumTinAntimonyTelluriumIodineXenon
CaesiumBariumLanthanumCeriumPraseodymiumNeodymiumPromethiumSamariumEuropiumGadoliniumTerbiumDysprosiumHolmiumErbiumThuliumYtterbiumLutetiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGoldMercury (element)ThalliumLeadBismuthPoloniumAstatineRadon
FranciumRadiumActiniumThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrenciumRutherfordiumDubniumSeaborgiumBohriumHassiumMeitneriumDarmstadtiumRoentgeniumCoperniciumNihoniumFleroviumMoscoviumLivermoriumTennessineOganesson


Be

Mg
lithium ← beryllium → boron
Atomic number (Z)4
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)1101001 k10 k100 k
at T (K)146216081791202323272742
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 structurehexagonal close-packed(hcp)
Hexagonal close packed crystal structure for beryllium
Speed of soundthin 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)
Main isotopes of beryllium
Iso­topeDecay
abun­dancehalf-life(t1/2)modepro­duct
7Betrace53.22 dε7Li
8Be0 (extinct)81.9 asα4He
9Be100%stable
10Betrace1.387×106 yβ10B
 Category: Beryllium
 | references

Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form minerals. Notable gemstones high in beryllium include beryl (aquamarineemerald) and chrysoberyl. It is a relatively rare element in the universe, usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Within the cores of stars, beryllium is depleted as it is fused into heavier elements. Beryllium constitutes about 0.0004 percent by mass of Earth's crust. The world's annual beryllium production of 220 tons is usually manufactured by extraction from the mineral beryl, a difficult process because beryllium bonds strongly to oxygen.

In structural applications, the combination of high flexural rigiditythermal stabilitythermal conductivity and low density (1.85 times that of water) make beryllium metal a desirable aerospace material for aircraft components, missilesspacecraft, and satellites.[6] Because of its low density and atomic mass, beryllium is relatively transparent to X-rays and other forms of ionizing radiation; therefore, it is the most common window material for X-ray equipment and components of particle detectors.[6] When added as an alloying element to aluminiumcopper (notably the alloy beryllium copper), iron, or nickel, beryllium improves many physical properties.[6] For example, tools and components made of beryllium copper alloys are strong and hard and do not create sparks when they strike a steel surface. In air, the surface of beryllium oxidizes readily at room temperature to form a passivation layer 1–10 nm thick that protects it from further oxidation and corrosion. The metal oxidizes in bulk (beyond the passivation layer) when heated above 500 °C (932 °F), and burns brilliantly when heated to about 2,500 °C (4,530 °F).

The commercial use of beryllium requires the use of appropriate dust control equipment and industrial controls at all times because of the toxicity of inhaled beryllium-containing dusts that can cause a chronic life-threatening allergic disease in some people called berylliosis.[7]Berylliosis causes pneumonia and other associated respiratory illness.