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neon(nē`ŏn) [Gr.,=new], gaseous chemical element; symbol Ne; at. no. 10; at. wt. 20.1797; m.p. −248.67°C;; b.p. −246.048°C;; density 0.8999 grams per liter at STPSTP
or standard temperature and pressure,
standard conditions for measurement of the properties of matter. The standard temperature is the freezing point of pure water, 0°C; or 273.15°K;.
..... Click the link for more information. ; valence 0. Neon is a colorless, odorless, and tasteless gas. It is one of the inert gasesinert gas
or noble gas,
any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are: helium, neon, argon, krypton, xenon, and radon. They are colorless, odorless, tasteless gases and were once believed to be entirely inert, i.e.
..... Click the link for more information. in Group 18 of the periodic tableperiodic table,
chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled
..... Click the link for more information. ; it does not form compounds in the normal chemical sense. A small amount of neon in a partially evacuated glass tube emits a bright reddish-orange glow while conducting electricity. Neon is a rare gas present in the atmosphere to a very limited extent. It is obtained as a byproduct in the production of liquid air. The greatest commercial use of neon is in advertising signs (see lightinglighting,
light produced by artificial means to allow visibility in enclosures and at night. For stage lighting, see scene design and stage lighting. Early Sources of Artificial Lighting
..... Click the link for more information. ). It is also used in high-intensity beacons, in some electron tubes, in Geiger counters, in automotive ignition timing lights, and in high-voltage warning indicators. It is used for particle detection in high-energy physics research. Neon finds use in laserslaser
[acronym for light amplification by stimulated emission of radiation], device for the creation, amplification, and transmission of a narrow, intense beam of coherent light. The laser is sometimes referred to as an optical maser.
..... Click the link for more information. both as a light-emitting agent and as a coolant. Liquid neon is a particularly good cryogenic refrigerant since it will absorb more heat without vaporizing than an equal volume of liquid helium or liquid hydrogen. Neon was discovered in 1898 by William RamsayRamsay, Sir William,
1852–1916, Scottish chemist. He was professor of chemistry at University College, Bristol (1880–87), and at University College, London (1887–1912).
..... Click the link for more information. and M. W. Travers.
(Latin, neonum), Ne, a chemical element of Group VIII in the Mendeleev periodic system. An inert gas: atomic number, 10; atomic weight, 20.179. On earth it is found mainly in the atmosphere, which is estimated to contain 7.1 × 1011 tons of neon. The neon content of air is about 16 cm3/m3. Atmospheric neon is a mixture of three stable isotopes—20Ne, 21Ne, and 22Ne; the first isotope predominates (90.92 percent). Neon was discovered in 1898 by the British scientists W. Ramsay and M. Travers during their study of the highly volatile fraction of liquid air. The name “neon” is derived from the Greek neos, “new.”
Under ordinary conditions, neon is a colorless, odorless gas. At 0°C and 760 mm of mercury (101 kilonewtons per sq m), the density of neon is 0.900 g/l; melting point, —248.6°C; boiling point, -245.9°C (at 101 KN/m2); solubility in water, 10.4 ml/l. Solid neon has a cubic crystal lattice; the lattice constant a of the unit cell is 4.52 angstroms at —253°C. The neon molecule is monatomic; the outer electron shell of the neon atom contains eight electrons and is highly stable. Neon compounds have not yet been synthesized.
Neon is produced by the fractionation of air. Its largest single use is in electrical engineering. Neon-filled lamps emitting red light are used at harbors, airports, and other locations. Liquid neon is coming to be used in the production of low temperatures.