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Periodic Table of Elements

Element Astatine - At

Comprehensive data on the chemical element Astatine is provided on this page; including scores of properties, element names in many languages, most known nuclides of Astatine. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

Astatine Menu

• Astatine Page One
  • Overview of Astatine
  • Astatine's Name in Other Languages
  • Atomic Structure of Astatine
  • Chemical Properties of Astatine
  • Physical Properties of Astatine
  • Regulatory / Health
  • Who/When/Where/How
• Astatine Page Two
  • Nuclides / Isotopes
  • Potential Parent Nuclides

Overview of Astatine

• Atomic Number: 85
• Group: 17
• Period: 6
• Series:Halogens

Astatine's Name in Other Languages

• Latin: Astatium
• Czech: Astat
• Croatian: Astat
• French: Astatine
• German: Astatin - r
• Italian: Astato
• Norwegian: Astat
• Portuguese: Astato
• Russian: Астат
• Spanish: Astato
• Swedish: Astat

Atomic Structure of Astatine

• Atomic Radius: 1.43Å
• Atomic Volume:
• Covalent Radius: 1.45Å
• Cross Section (Thermal Neutron Capture)σ_a/barns:
• Crystal Structure:

• Electron Configuration:

  1s² 2s²p⁶ 3s²p⁶d¹⁰ 4s²p⁶d¹⁰f¹⁴ 5s²p⁶d¹⁰ 6s²p⁵

• Electrons perEnergy Level: 2,8,18,32,18,7

  Shell Model
  

• Ionic Radius:
• Filling Orbital: 6p⁵
• Number ofElectrons (with no charge): 85
• Number ofNeutrons (most common/stable nuclide): 125
• Number ofProtons: 85
• Oxidation States:±1,3,5,7
• Valence Electrons: 6s²p⁵

  Electron Dot Model
  

Chemical Properties of Astatine

• Electrochemical Equivalent: 7.8346g/amp-hr
• Electron Work Function:
• Electronegativity: 2.2 (Pauling); 1.96 (Allrod Rochow)
• Heat of Fusion: 114kJ/mol
• Incompatibilities:

• Ionization Potential
  • First: 9.65
• Valence Electron Potential (-eV):

Physical Properties of Astatine

• Atomic Mass Average: 209.9871
• Boiling Point: 610K 337°C 639°F
• Coefficient of lineal thermal expansion/K^-1: N/A
• Conductivity

  Electrical:
  Thermal: 0.017 W/cmK

• Description:

  Radioactive member of the halogen group.

• Enthalpy of Atomization: 92 kJ/mole @ 25°C
• Flammablity Class:
• Freezing Point:see melting point
• Heat of Vaporization: kJ/mol
• Melting Point: 575K 302°C 576°F
• Physical State (at 20°C & 1atm): Solid
• Specific Heat:

Regulatory / Health

• CAS Number
  • 7440-68-8
• NFPA 704
  • Health:
  • Fire:
  • Reactivity:
  • Special Hazard: Radioactive<
  • OSHAPermissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSHRecommended Exposure Limit (REL)
    • No limits set by NIOSH
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm^-3: nil
    • Bone/p.p.m: nil
    • Liver/p.p.m: nil
    • Muscle/p.p.m: nil
    • Daily Dietary Intake: nil
    • Total Mass In Avg. 70kg human: nil

  Who / Where / When / How

  • Discoverer: D.R.Corson, K.R.MacKenzie, E.Segré
  • Discovery Location: Berkeley California United States
  • Discovery Year: 1940
  • Name Origin:

    Greek: astatos (unstable).

  • Abundance of Astatine:
    • Earth's Crust/p.p.m.: N/A
    • Seawater/p.p.m.: nil
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E¹²): N/A
  • Sources of Astatine:

    Does not occur in nature. Produced by bombarding bismuth with alpha particles. Total world production to date estimated to be around 50 nanograms (50E-9 g).

  • Uses of Astatine:

    None

  • Additional Notes:

    Astatine can be found in uranium and thorium minerals as part of the natural decay series, however, the total amount present at any point in time in the entire earth's crust is estimated to be less than 30 grams.

  Astatine Menu

  • Astatine Page One
    • Overview of Astatine
    • Astatine's Name in Other Languages
    • Atomic Structure of Astatine
    • Chemical Properties of Astatine
    • Physical Properties of Astatine
    • Regulatory / Health
    • Who/When/Where/How
  • Astatine Page Two
    • Nuclides / Isotopes
    • Potential Parent Nuclides

  References

  A list of reference sources used to compile the data provided on our periodic table of elements can be found on the mainperiodic table page.

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  • Chemical Database
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