Beryllium (Be)

Element Beryllium – Be

Beryllium Symbol

Overview of Beryllium

·     Atomic Number:4 ,   Group: 2,  Period: 2, Series: Alkali Earth Metals

·                            Spanish: Berílio

·                            Swedish: Beryllium

Atomic Structure of Beryllium

·                            Atomic Radius: 1.4Å

·                            Atomic Volume: 5cm³/mol

·                            Covalent Radius: 0.9Å

·                            Cross Section (Thermal Neutron Capture)σ_a/barns: 0.0092

·                            

·                            Electron Configuration:

1s² 2s²

·                            Electrons per Energy Level: 2,2

·                            Ionic Radius: 0.35Å

·                            Filling Orbital: 2s²

·                            Number of Electrons (with no charge): 4

·                            Number of Neutrons (most common/stable nuclide): 5

·                            Number of Protons: 4

·                            Oxidation States: 2

·                            Valence Electrons: 2s²

Electron Dot Model

Chemical Properties of Beryllium

·                            Electrochemical Equivalent: 0.16812g/amp-hr

·                            Electron Work Function: 4.98eV

·                            Electronegativity: 1.57 (Pauling); 1.47 (Allrod Rochow)

·                            Heat of Fusion: 12.2kJ/mol

·                            Incompatibilities:

acids and strong bases, carbon tetrachloride, phos- phorous 3-chlorolithium, caustics, chlorinated hydrocarbons, oxidizers, molten lithium.

·                            Ionization Potential

o                                              First: 9.322

o                                              Second: 18.211

o                                              Third: 153.893

·                            Valence Electron Potential (-eV): 82

Physical Properties of Beryllium

·                            Atomic Mass Average: 9.012182

·                            Boiling Point: 3243K 2970°C 5378°F

·                            Coefficient of lineal thermal expansion/K^-1: 0.0000116E^-6

·                            Conductivity

Electrical: 0.313 10⁶/cm Ω
Thermal: 2.01 W/cmK

·                            Density: 1.848g/cc @ 300K

·                            Description:

Strong, hard, gray-white metal. Lightest rigid metal. Formerly called glucinium (Gl).

·                            Elastic Modulus:

o                                              Bulk: 110/GPa

o                                              Rigidity: 156/GPa

o                                              Youngs: 318/GPa

·                            Enthalpy of Atomization: 326.4 kJ/mole @ 25°C

·                            Enthalpy of Fusion: 11.72 kJ/mole

·                            Enthalpy of Vaporization: 294.7 kJ/mole

·                            Flammablity Class: Non-combustible solid (except as dust)

·                            Freezing Point: see melting point

·                            Hardness Scale

o                                              Brinell: 600 MN m^-2

o                                              Mohs: 5.5

o                                              Vickers: 1670 MN m^-2

·                            Heat of Vaporization: 292.4kJ/mol

·                            Melting Point: 1551K 1278°C 2332°F

·                            Molar Volume: 4.88 cm³/mole

·                            Physical State (at 20°C & 1atm): Solid

·                            Specific Heat: 1.82J/gK

·                            Vapor Pressure 4.18kPa

Regulatory / Health

·                            CAS Number

o                                              7440-41-7 metal

·                            UN/NA ID and ERG Guide Number

o                                              UN1567  / 134 powder

·                            RTECS: DS1750000

·                            NFPA 704

o                                              Health: 4

o                                              Fire: 1

o                                              Reactivity: 1

o                                              Special Hazard:

·                            OSHA Permissible Exposure Limit (PEL)

o                                              TWA: 0.002 mg/m³

o                                              Ceiling: 0.005 mg/m³

o                                              Notes: Ceiling 0.025 mg/m³ 30-min max peak

·                            OSHA PEL Vacated 1989

o                                              TWA: 0.002 mg/m³

o                                              Ceiling: 0.005 mg/m³

o                                              Notes: Ceiling 0.025 mg/m3 30-min max peak

·                            NIOSH Recommended Exposure Limit (REL)

o                                               

o                                              Notes: Not to exceed 0.0005 mg/m³

o                                              IDLH: 4 mg/m³ (Potential NIOSH carcinogen)

·                            Routes of Exposure: Inhalation; Skin and/or eye contact

·                            Target Organs: Eyes, skin, respiratory system

·                            Levels In Humans:
Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.

o                                              Blood/mg dm^-3: <1E^-5

o                                              Bone/p.p.m: 0.003

o                                              Liver/p.p.m: 0.0016

o                                              Muscle/p.p.m: 0.00075

o                                              Daily Dietary Intake: 0.01 mg

o                                              Total Mass In Avg. 70kg human: 0.036 mg

Who / Where / When / How

·                            Discoverer: Nicholas Louis Vauquelin

·                            Discovery Location: Paris France

·                            Discovery Year: 1797

·                            Name Origin:

From the mineral beryl.

·                            Abundance of Beryllium:

o                                              Earth's Crust/p.p.m.: 2.6

o                                              Seawater/p.p.m.:

§                                                                  Atlantic Suface: 8.8E-08

§                                                                  Atlantic Deep: 1.75E-07

§                                                                  Pacific Surface: 3.5E-08

§                                                                  Pacific Deep: 2.2E-07

o                                              Atmosphere/p.p.m.: N/A

o                                              Sun (Relative to H=1E¹²): 14

·                            Sources of Beryllium:

Found mostly in minerals like beryl [AlBe₃(Si₆O₁₈)] and chrysoberyl (Al₂BeO₄). Total world production per year is around 364 tons. Main mining areas are Brazil,USA, Madagascar, Germany, Czech Republic, Russia and India. Total world reserves estimated to be around 400,000 tons.

·                            Uses of Beryllium:

Its ability to absorb large amounts of heat makes it useful in spacecraft, missiles, aircraft, etc. Emeralds are beryl crystals with chromium traces giving them their green color. Also used in light weight metal alloys, X-ray tube windows, watch springs and sparkless tools.

                         

Lithium

Lithium Symbol
               

                   

             

     

  Lithium  Battery

Atomic Number: 3

Symbol: Li

Atomic Weight: 6.941

Discovery: 1817, Arfvedson (Sweden)

Electron Configuration: [He]2s¹

Word Origin Greek: lithos, stone

Properties: Lithium has a melting point of 180.54°C, boiling point of 1342°C, specific gravity of 0.534 (20°C), and valence of 1. It is the lightest of the metals, with a density approximately half that of water. Under ordinary conditions, lithium is the least dense of the solid elements. It has the highest specific heat of any solid element. Metallic lithium is silvery in appearance. It reacts with water, but not as vigorously as does sodium. Lithium imparts a crimson color to flame, although the metal itself burns a bright white. Lithium is corrosive and requires special handling. Elemental lithium is extremely flammable.

Uses: Lithium is used in heat transfer applications. It is used as an alloying agent, in synthesizing organic compounds, and is added to glasses and ceramics. Its high electrochemical potential makes it useful for battery anodes. Lithium chloride and lithium bromide are highly hygroscopic, so are used as drying agents. Lithium stearate is used as a high-temperature lubricant. Lithium has medical applications, as well.

Sources: Lithium does not occur free in nature. It is found in small amounts in practically all igneous rocks and in the waters of mineral springs. The minerals that contain lithium include lepidolite, petalite, amblygonite, and spodumene. Lithium metal is produced electrolytically from the fused chloride.

Element Classification: Alkali Metal

Density (g/cc): 0.534

Appearance: soft, silvery-white metal

Atomic Radius (pm): 155

Atomic Volume (cc/mol): 13.1

Covalent Radius (pm): 163

Ionic Radius: 68 (+1e)

Specific Heat (@20°C J/g mol): 3.489

Fusion Heat (kJ/mol): 2.89

Evaporation Heat (kJ/mol): 148

Debye Temperature (°K): 400.00

Pauling Negativity Number: 0.98

First Ionizing Energy (kJ/mol): 519.9

Oxidation States: 1

Lattice Structure: Body-Centered Cubic

Lattice Constant (Å): 3.490

Magnetic Ordering: paramagnetic

Electrical Resistivity (20°C): 92.8 nΩ·m

Thermal Conductivity (300 K): 84.8 W·m−1·K−1

Thermal Expansion (25°C): 46 µm·m−1·K−1

Speed of Sound (thin rod) (20°C): 6000 m/s

Young's Modulus: 4.9 GPa

Shear Modulus: 4.2 GPa

Bulk Modulus: 11 GPa

Mohs Hardness: 0.6

CAS Registry Number: 7439-93-2

Helium

                                    Helium  Symbol



Helium

Helium Atomic Number: 2

Helium Symbol: He

Helium Atomic Weight: 4.00260

Helium Discovery: Janssen, 1868, some sources say Sir William Ramsey, Nils Langet, P.T. Cleve 1895

Helium Electron Configuration: 1s²

Word Origin: Greek: helios, sun. Helium was first detected as a new spectral line during a solar eclipse.

Isotopes: 7 isotopes of helium are known.

Properties: Helium is a very light, inert, colorless gas. Helium has the lowest melting point of any element. It is the only liquid that cannot be solidified by lowering the temperature. It remains liquid down to absolute zero at ordinary pressures, but can be solidified by increasing the pressure. The specific heat of helium gas is unusually high. The density of helium vapor at the normal boiling point is also very high, with the vapor expanding greatly when heated to room temperature. Although helium normally has a valence of zero, it has a weak tendency to combine with certain other elements.

Uses: Helium is widely used in cryogenic research because its boiling point is near absolute zero. It is used in the study of superconductivity, as an inert gas shield for arc welding, as a protective gas in growing silicon and germanium crystals and producing titanium and zirconium, for pressuring liquid fuel rockets, for use in magnetic resonance imaging (MRI), as a cooling medium for nuclear reactors, and as a gas for supersonic wind tunnels. A mixture of helium and oxygen is used as an artificial atmosphere for divers and others working under pressure. Helium is used for filling balloons and blimps.

Sources: Except for hydrogen, helium is the most abundant element in the universe. It is an important component in the proton-proton reaction and the carbon cycle, which account for the energy of the sun and stars. Helium is extracted from natural gas. In fact, all natural gas contains at least trace quantities of helium. The fusion of hydrogen into helium is the sources of a hydrogen bomb's energy. Helium is a disintegration product of radioactive substances, so it is found in ores of uranium, radium, and other elements.

Element Classification: Noble Gas or Inert Gas

Usual Phase: gas

Density (g/cc): 0.147 (@ -270°C)

Melting Point (°K): 0.95

Boiling Point (°K): 4.216

Critical Point: 5.19 K, 0.227 MPa

Atomic Volume (cc/mol): 31.8

Ionic Radius: 93

Specific Heat (@20°C J/g mol): 5.188

Heat of Fusion: 0.0138 kJ/mol

Evaporation Heat (kJ/mol): 0.08

First Ionizing Energy (kJ/mol): 2361.3

Lattice Structure: Hexagonal

Lattice Constant (Å): 3.570

Lattice C/A Ratio: 1.633

Crystal Structure: close-packed hexagonal

Magnetic Ordering: diamagnetic

CAS registry number: 7440-59-7

Sources: Los Alamos National Laboratory (2001), Crescent Crescent Chemical Company (2001), Lange's Handbook of Chemistry (1952)