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Neon, ₁₀Ne

Neon
Appearance	colorless gas exhibiting an orange-red glow when placed in an electric field
Standard atomic weight Ar°(Ne)
	20.1797±0.0006 20.180±0.001 (abridged)
Neon 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 He ↑ Ne ↓ Ar fluorine ← neon → sodium
Atomic number (Z)	10
Group	group 18 (noble gases)
Period	period 2
Block	p-block
Electron configuration	[He] 2s 2p
Electrons per shell	2, 8
Physical properties
Phase at STP	gas
Melting point	24.56 K ​(−248.59 °C, ​−415.46 °F)
Boiling point	27.104 K ​(−246.046 °C, ​−410.883 °F)
Density (at STP)	0.9002 g/L
when liquid (at b.p.)	1.207 g/cm
Triple point	24.556 K, ​43.37 kPa
Critical point	44.4918 K, 2.7686 MPa
Heat of fusion	0.335 kJ/mol
Heat of vaporization	1.71 kJ/mol
Molar heat capacity	20.79 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 12 13 15 18 21 27
Atomic properties
Oxidation states	common: (none) 0
Ionization energies	1st: 2080.7 kJ/mol 2nd: 3952.3 kJ/mol 3rd: 6122 kJ/mol (more)
Covalent radius	58 pm
Van der Waals radius	154 pm
Spectral lines of neon
Other properties
Natural occurrence	primordial
Crystal structure	​face-centered cubic (fcc) (cF4)
Lattice constant	a = 453.77 pm (at triple point)
Thermal conductivity	49.1×10 W/(m⋅K)
Magnetic ordering	diamagnetic
Molar magnetic susceptibility	−6.74×10 cm/mol (298 K)
Bulk modulus	654 GPa
Speed of sound	435 m/s (gas, at 0 °C)
CAS Number	7440-01-9
History
Prediction	William Ramsay (1897)
Discovery and first isolation	William Ramsay & Morris Travers (1898)
Isotopes of neon v e
Main isotopes Decay abun­dance half-life (t1/2) mode pro­duct Ne 90.5% stable Ne 0.27% stable Ne 9.25% stable
Category: Neon view talk edit | references

Neon (IPA: /ˈniːɒn/) is the chemical element that has the symbol Ne and atomic number 10. A very common element in the universe, it is rare on Earth. A colorless, inert noble gas under standard conditions, neon gives a distinct reddish glow when used in vacuum discharge tubes and neon lamps. It is commercially extracted from air, in which it is found in trace amounts.

Notable characteristics

Neon is the second-lightest noble gas, glows reddish-orange in a vacuum discharge tube and has over 40 times the refrigerating capacity of liquid helium and three times that of liquid hydrogen (on a per unit volume basis). In most applications it is a less expensive refrigerant than helium. Neon plasma has the most intense light discharge at normal voltages and currents of all the rare gases. The average color of this light to the human eye is red-orange; it contains a strong green line which is hidden, unless the visual components are dispersed by a spectroscope.

Applications

The reddish-orange color that neon emits in neon lights is widely used to make advertising signs and is used in long tubular strips in car modification. The word "neon" is used generically for these types of lights even though many other gases are used to produce different colors of light.

Neon may also be used in vacuum tubes, high-voltage indicators, lightning arrestors, wave meter tubes, television tubes, and helium-neon lasers. Liquefied neon is commercially used as a cryogenic refrigerant in applications not requiring the lower temperature range attainable with more expensive liquid helium refrigeration.

Neon's triple point temperature of 24.5561 K is a defining fixed point in the International Temperature Scale of 1990.

History

Neon (Greek νέον(neon) meaning "new one") was discovered in 1898 by Scottish chemist William Ramsay (1852 - 1916) and English chemist Morris W. Travers in London, England. Neon was discovered when Ramsay chilled a sample of the atmosphere until it became a liquid, then warmed the liquid and captured the gases as they boiled off. The three gases were krypton, xenon, and neon.

Occurrence

Neon is actually abundant on a universal scale: the fifth most abundant chemical element in the universe by mass, after hydrogen, helium, oxygen, and carbon (see chemical element). Its relative rarity on Earth, like that of helium, is due to its relative lightness and chemical inertness, both properties keeping it from being trapped in the condensing gas and dust clouds of the formation of smaller and warmer solid planets like Earth. Mass abundance in the universe is about 1 part in 750 and in the Sun and presumably in the proto-solar system nebula, about 1 part in 600. The Galileo spacecraft atmospheric entry probe found that even in the upper atmosphere of Jupiter, neon is reduced by about a factor of 10, to 1 part in 6,000 by mass. This may indicate that even the ice-planetesmals which brought neon into Jupiter from the outer solar system, formed in a region which was too warm for them to have kept their neon (abundances of heavier inert gases on Jupiter are several times that found in the Sun).

Neon is a monatomic gas at standard conditions. Neon is rare on Earth, found in the Earth's atmosphere at 1 part in 65,000 (by volume) or 1 part in 83,000 by mass. It is industrially produced by cryogenic fractional distillation of liquefied air.

Compounds

Neon is a noble gas, and therefore generally considered to be inert. However, there is evidence that it may form a compound with fluorine, and evidence is mounting in favor of the existence of neon compounds. The ions, Ne, (NeAr), (NeH), and (HeNe), have been observed from optical and mass spectrometric studies, and neon is also known to form an unstable hydrate.

Isotopes

Neon has three stable isotopes: Ne (90.48%), Ne (0.27%) and Ne (9.25%). Ne and Ne are nucleogenic and their variations are well understood. In contrast, Ne is not known to be nucleogenic and the causes of its variation in the Earth have been hotly debated. The principal nuclear reactions which generate neon isotopes are neutron emission, alpha decay reactions on Mg and Mg, which produce Ne and Ne, respectively. The alpha particles are derived from uranium-series decay chains, while the neutrons are mostly produced by secondary reactions from alpha particles. The net result yields a trend towards lower Ne/Ne and higher Ne/Ne ratios observed in uranium-rich rocks such as granites. Isotopic analysis of exposed terrestrial rocks has demonstrated the cosmogenic production of Ne. This isotope is generated by spallation reactions on magnesium, sodium, silicon, and aluminium. By analyzing all three isotopes, the cosmogenic component can be resolved from magmatic neon and nucleogenic neon. This suggests that neon will be a useful tool in determining cosmic exposure ages of surficial rocks and meteorites.

Similar to xenon, neon content observed in samples of volcanic gases are enriched in Ne, as well as nucleogenic Ne, relative to Ne content. The neon isotopic content of these mantle-derived samples represent a non-atmospheric source of neon. The Ne-enriched components are attributed to exotic primordial rare gas components in the Earth, possibly representing solar neon. Elevated Ne abundances are found in diamonds, further suggesting a solar neon reservoir in the Earth.

References

1. "Standard Atomic Weights: Neon". CIAAW. 1985.
2. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
3. Hammond, C. R. (2000). The Elements, in Handbook of Chemistry and Physics 81st edition (PDF). CRC press. p. 19. ISBN 0849304814.
4. ^ Preston-Thomas, H. (1990). "The International Temperature Scale of 1990 (ITS-90)". Metrologia. 27 (1): 3–10. Bibcode:1990Metro..27....3P. doi:10.1088/0026-1394/27/1/002. Cite error: The named reference "ITS90" was defined multiple times with different content (see the help page).
5. ^ Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, Florida: CRC Press. p. 4.122. ISBN 1-4398-5511-0.
6. Shuen-Chen Hwang, Robert D. Lein, Daniel A. Morgan (2005). "Noble Gases". in Kirk Othmer Encyclopedia of Chemical Technology, pages 343–383. Wiley. doi:10.1002/0471238961.0701190508230114.a01.pub2
7. Ne(0) has been observed in Cr(CO)₅Ne; see Perutz, Robin N.; Turner, James J. (August 1975). "Photochemistry of the Group 6 hexacarbonyls in low-temperature matrices. III. Interaction of the pentacarbonyls with noble gases and other matrices". Journal of the American Chemical Society. 97 (17): 4791–4800. doi:10.1021/ja00850a001.
8. Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.
9. Magnetic susceptibility of the elements and inorganic compounds, in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0486-5.
10. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
11. Ramsay, William; Travers, Morris W. (1898). "On the Companions of Argon". Proceedings of the Royal Society of London. 63 (1): 437–440. doi:10.1098/rspl.1898.0057. ISSN 0370-1662. S2CID 98818445.
12. "Neon: History". Softciências. Retrieved 2007-02-27.
13. 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.
14. "Neon". Los Almos National Laboratory. 15. Retrieved 2007-03-05. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help); Unknown parameter |month= ignored (help)
15. "NASSMC: News Bulletin". 30. Retrieved 2007-03-05. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help); Unknown parameter |month= ignored (help)
16. "Plasma". Retrieved 2007-03-05.
17. William Ramsay, Morris W. Travers (1898). "On the Companions of Argon". Proceedings of the Royal Society of London. 63: 437–440.
18. "Neon: History". Softciências. Retrieved 2007-02-27.
19. Morse, David (26). "Galileo Probe Science Result". Galileo Project. Retrieved 2007-02-27. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help); Cite has empty unknown parameter: |coauthors= (help); Unknown parameter |month= ignored (help)
20. Hammond, C. R. "The Elements" (PDF). Fermi National Accelerator Lab. p. 19. Retrieved 2007-02-27. {{cite web}}: Cite has empty unknown parameters: |month= and |coauthors= (help)
21. "Periodic Table: Neon." Lawrence Livermore National Laboratory. Last updated on December 15, 2003. Retrieved on August 31, 2007.
22. "Neon: Isotopes". Softciências. Retrieved 2007-02-27.
23. Anderson, Don L. "Helium, Neon & Argon". Mantleplumes.org. Retrieved 2006-07-02.

External links

• WebElements.com – Neon
• It's Elemental – Neon
• Computational Chemistry Wiki
• Los Alamos National Laboratory – Neon
• USGS Periodic Table - Neon

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