• Class: Inert Gases
• Period: 2
• IUPAC group: 18
• Traditional: 0

• Discovered in: 1898 by Ramsay, Travers
• Origin of name: Greek: neos, (new)
• Historical or alternate name:

Air, 1 part in 65,000

Colorless, odorless gas. Chemically inert. Non-reactive even with Fluorine.

• Atmosphere: 18 ppm
• Primitive mantle: ~0.0 ppm
• Sea water: 0.04 ppm
• Metallic meteorite: 203.0 ppm
• Continental crust: 7.00E-5 ppm
• Solar photosphere: 7.57 log of abundance
• Oceanic crust: ~0.0 ppm
• Solar system: 3.760E+6 relative to Si=1.0e6

   Hazards

Inert nonflammable gas. Asphyxiant..

   Human daily limits

• Lower:
• Upper:

Neon Physical Properties

 Transitional Data

• State: Gas
• Density: 0.9002 g/L

 Molar enthalpy

• Atomization: 0.0 kJ mol-1
• Fusion: 0.324 kJ mol-1
• Vaporization: 1.736 kJ mol-1

 Transition points

• Melting point: 24.48 K
• Boiling point: 27.10 K
• Critical temperature: 44.4 K

 Molar properties

• Atomic weight: 20.1797 g/mole
• Molar volume: 13.460 cm3 mol-1

 Crystal structure sequence

face-centered-cubic

 Thermodynamics

• State: gas
  • Enthalpy 0
  • Gibbs function 0
  • Entropy 146.328
  • Heat Capacity 20.786

 Miscellaneous physical

• Electrical resistivity: µ-ohms/cm
• Debye temperature: 75.0 K
• Thermal conductivity: 0.0491 W / m / K
• Coefficient of linear expansion: Coef. per K
• Mass magnetic susceptibility: -4.2e-9
• X-ray diffraction mass absorption coefficients:
• CuK: 22.9 (µ/p)/cm2 g-1
• MoK: 2.47 (µ/p)/cm2 g-1

Neon Chemical Properties

 Chemical basics:

• Oxidation states: 0
• Molecular wt: 20.1797 g/mole

 Radii

• Covalent: pm
• Atomic: 154.0 pm
• Van der Waals: 160 pm

 Ions:

 Covalent bonds

 Effective nuclear charge

• Slater: 5.85
• Clementi: 5.76
• Froese-Fischer: 5.18

 Electronegativity

• Pauling:
• Allred-Rochow:

 Standard reactions

Neon Nuclear Properties

• Known 8
• Listed 3

• Known 17 - 24
• Listed 20 - 22

• % Occ.:Natural 90.51%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 0.27%
• Mossbauer NRA:
• Nuclear spin/Quantum no.: 3/2
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 9.22%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• Isotope Cross-section 0.038 barns

• Absolute sensitivity: 6.43e-6 1H=1.0
• Relative sensitivity: 2.50e-3 1H=1.0
• Receptivity: 0.0359 13C=1.0
• Magnetogyric ratio: -2.1118e7 rad / T / s
• Quadropole moment: 9.e-30 m2
• Frequency: 7.894 MHz
• Reference:

Neon Energy Properties

Electrons

• Ground state electron configuration: 1s2 2s2 2p6
• Electron affinity: -29 kJ mol-1
• Filling orbitals:

 Ionization energies

 Atomic energy levels