Neon

For other uses, see Neon (disambiguation).
General Name, Symbol, Number neon, Ne, 10 Chemical series noble gases Group, Period, Block 18, 2, p Appearance colorless
Atomic mass 20.1797(6) g/mol Electron configuration 1s2 2s2 2p6 Electrons per shell 2, 8 Physical properties Phase gas Density (0 °C, 101.325 kPa)
0.9002 g/L Melting point 24.56 K
(-248.59 °C, -415.46 °F) Boiling point 27.07 K
(-246.08 °C, -410.94 °F) Heat of fusion 0.335 kJ/mol Heat of vaporization 1.71 kJ/mol Heat capacity (25 °C) 20.786 J/(mol·K) Atomic properties Crystal structure cubic face centered Oxidation states no data Ionization energies
(more) 1st: 2080.7 kJ/mol 2nd: 3952.3 kJ/mol 3rd: 6122 kJ/mol Atomic radius (calc.) 38 pm Covalent radius 69 pm Van der Waals radius 154 pm Miscellaneous Magnetic ordering nonmagnetic Thermal conductivity (300 K) 49.1 mW/(m·K) Speed of sound (gas, 0 °C) 435 m/s CAS registry number 7440-01-9 Notable isotopes References

Neon is the chemical element in the periodic table that has the symbol Ne and atomic number 10. A colorless nearly inert noble gas, neon gives a distinct reddish glow when used in vacuum discharge tubes and neon lamps and is found in air 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 has the most intense discharge at normal voltages and currents of all the rare gases.

Applications

Neon is often used in signs

The reddish-orange color that neon emits in neon lights is widely used to make advertising signs. The word "neon" is also used generically for these types of lights when in reality many other gases are used to produce different colors of light. Other uses:

History

Neon (Greek neos meaning "new") was discovered by Scottish chemist William Ramsay and English chemist Morris Travers in 1898.

Occurrence

Neon is usually found in the form of a gas with molecules consisting of a single neon atom. Neon is a rare gas that is found in the Earth's atmosphere at 1 part in 65,000 and is produced by supercooling air and fractionally distilling it from the resulting cryogenic liquid. Neon, like water vapor, is lighter than air; unlike water vapor, which condenses into a liquid below the stratosphere and is thus trapped in Earth's atmosphere, neon may slowly leak out into space, which explains its scarcity on Earth. Argon, in contrast, is heavier than air and so remains within Earth's atmosphere.

Compounds

The ions, Ne+, (NeAr)+, (NeH)+, and (HeNe+), have been observed from optical and mass spectrometric research. In addition, neon forms an unstable hydrate.

Isotopes

Neon has three stable isotopes: 20Ne (90.48%), 21Ne (0.27%) and 22Ne (9.25%). 21Ne and 22Ne are nucleogenic and their variations are well understood. In contrast, 20Ne 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 24Mg and 25Mg, which produce 21Ne and 22Ne, 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 20Ne/22Ne and higher 21Ne/22Ne ratios observed in uranium-rich rocks such as granites. Isotopic analysis of exposed terrestrial rocks has demonstrated the cosmogenic production of 21Ne. 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 20Ne, as well as nucleogenic 21Ne, relative to 22Ne content. The neon isotopic content of these mantle-derived samples represent a non-atmospheric source of neon. The 20Ne-enriched components are attributed to exotic primordial rare gas components in the Earth, possibly representing solar neon. Elevated 20Ne abundances are also found in diamonds, further suggesting a solar neon reservoir in the Earth.

References


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Elevated 20Ne abundances are also found in diamonds, further suggesting a solar neon reservoir in the Earth. The categories are named for cities and areas associated with each design:. The 20Ne-enriched components are attributed to exotic primordial rare gas components in the Earth, possibly representing solar neon. Carpet dealers have developed a classification for Persian carpets based on design, type of fabric, and weaving technique. The neon isotopic content of these mantle-derived samples represent a non-atmospheric source of neon. The influence of Persian carpets is readily apparent in his carpet designs. Similar to xenon, neon content observed in samples of volcanic gases are enriched in 20Ne, as well as nucleogenic 21Ne, relative to 22Ne content. A fine and well-known example of the later was purchased by the Victoria and Albert Museum under the guidance of William Morris.

This suggests that neon will be a useful tool in determining cosmic exposure ages of surficial rocks and meteorites. She identified their unique structure and named it the "vase technique." Carpet types in this group include garden carpets (ornamented with formal gardens and water channels) and the ogival lattice carpets. By analyzing all three isotopes, the cosmogenic component can be resolved from magmatic neon and nucleogenic neon. The seven classes of Kerman carpet were defined by May Beattie. This isotope is generated by spallation reactions on magnesium, sodium, silicon, and aluminium. They are characterized by a red field with scrolling vine ornament and palmettes with dark green or blue borders. Isotopic analysis of exposed terrestrial rocks has demonstrated the cosmogenic production of 21Ne. The Herat carpets, or ones of similar design created in Lahore and Agra, India, are the most numerous in Western collections.

The net result yields a trend towards lower 20Ne/22Ne and higher 21Ne/22Ne ratios observed in uranium-rich rocks such as granites. One carpet, for example, is known to have been sold in Germany for $20,000 in 1969. The alpha particles are derived from uranium-series decay chains, while the neutrons are mostly produced by secondary reactions from alpha particles. The Kashan rugs are among the most valuable in existence. The principal nuclear reactions which generate neon isotopes are neutron emission, alpha decay reactions on 24Mg and 25Mg, which produce 21Ne and 22Ne, respectively. Most famously, for the three silk hunting carpet masterpieces depicting mounted hunters and animal prey (currently in the collections of the Vienna Museum of Applied Arts (aka the MAK), the Museum of Fine Arts, Boston, and the Stockholm Museum). In contrast, 20Ne is not known to be nucleogenic and the causes of its variation in the Earth have been hotly debated. Kashan is known for its silk carpet production.

21Ne and 22Ne are nucleogenic and their variations are well understood. Perhaps the most well-known of the Tabriz works are the twin Ardabil carpets most likely made for the shrine at Ardabil (today in the collections of the Victoria and Albert Museum in London and the Los Angeles County Museum). Neon has three stable isotopes: 20Ne (90.48%), 21Ne (0.27%) and 22Ne (9.25%). The majority of carpets from Tabriz have a central medallion and quartered corner medallions superimposed over a field of scrolling vine ornament, sometimes punctuated with mounted hunters, single animals, or animal combat scenes. In addition, neon forms an unstable hydrate. The major classical centers of carpet production in Persia were in Tabriz (1500-1550), Kashan (1525-1650), Herat (1525-1650), and Kerman (1600-1650). The ions, Ne+, (NeAr)+, (NeH)+, and (HeNe+), have been observed from optical and mass spectrometric research. Also see: Knots per sq cm).

Argon, in contrast, is heavier than air and so remains within Earth's atmosphere. When comparing carpets the only way to definitively identify the knot used is to splay open the pile by bending the rug against itself and looking at the base of the knot. Neon, like water vapor, is lighter than air; unlike water vapor, which condenses into a liquid below the stratosphere and is thus trapped in Earth's atmosphere, neon may slowly leak out into space, which explains its scarcity on Earth. Today, it is common to see carpets woven in both Turkey and Iran using either of the two knot styles. Neon is a rare gas that is found in the Earth's atmosphere at 1 part in 65,000 and is produced by supercooling air and fractionally distilling it from the resulting cryogenic liquid. However, given that a well made and taken care of carpet in either style can easily last several hundred years this is usually disregarded. Neon is usually found in the form of a gas with molecules consisting of a single neon atom. It is also common to see Anatolian rugs identified as longer lasting, which they probably are.

Neon (Greek neos meaning "new") was discovered by Scottish chemist William Ramsay and English chemist Morris Travers in 1898. The result of these factors has concequently created the ancient and international reputation of the 'persian carpet' in terms of quality. Other uses:. The traditional Anatolian style also reduces the number of Knots per sq cm. The word "neon" is also used generically for these types of lights when in reality many other gases are used to produce different colors of light. Ultimately, this process of 'double knotting' in traditional Anatolian/Turkish carpets results in a slightly more block like image when compared to the traditional 'single knotted' Persian carpet. The reddish-orange color that neon emits in neon lights is widely used to make advertising signs. This means that for every 'vertical strand' of thread in a carpet, an Anatolian carpet has two loops as opposed to the one loop for the various Persian rugs that use a Persian 'single' knot.

Neon has the most intense discharge at normal voltages and currents of all the rare gases. Typically, a traditional Persian carpet is tied with a singe looping knot (Persian or Senneh Knot), meanwhile the traditional Anatolian carpet is tied with a double looping knot (Turkish or Ghiordes Knot). In most applications it is a less expensive refrigerant than helium. The difference between Anatolian (Turkish) and Persian rugs is today largely one of tradition. 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). Many fine pieces of the Persian carpet are to be found in The Carpet Museum of Iran in Tehran. . Although carpet production has mostly become mechanized today, the traditional hand woven rugs are still widely found all around the world, and usually have higher prices than their machine woven counterparts.

A colorless nearly inert noble gas, neon gives a distinct reddish glow when used in vacuum discharge tubes and neon lamps and is found in air in trace amounts. According to this theory the art of carpet-weaving is at least 3500 years old. Neon is the chemical element in the periodic table that has the symbol Ne and atomic number 10. Most experts believe that the Pazyryk carpet is a late achievement of at least one thousand years of technique evolution and history. Los Alamos National Laboratory – Neon. The advanced weaving technique used in the Pazyryk carpet indicates a long history of evolution and experience in this art. Liquefied neon is commercially used as an economical cryogenic refrigerant. This carpet is 1.83×2 meters and has 36 symmetrical knots per cm².

Neon and helium are used to make a type of gas laser. Radiocarbon testing revealed that Pazyryk carpet was woven in the 5th century BC. television tubes. It was discovered in the grave of a Scythian prince by a group of Russian archaeologists under the supervision of Sergei Ivanovich Rudenko. wave meter tubes. In a unique archaeological excavation in 1949 however, the exceptional Pazyryk carpet was discovered among the ices of Pazyryk Valley, in Altai Mountains in Siberia. lightning arrestors. These pieces attracted the attention of researchers earlier this century, and now they are kept in the Museum of Turkish and Islamic Art in Istanbul and the Mowlana Museum in Konya.

high-voltage indicators. Among the oldest pieces discovered are those found in Eastern Turkestan, dating back to the third to fifth centuries AD, and also some of the hand-weavings of the Seljuks of Asia Minor on exhibit in Ala’edin Mosque in Konya and Ashrafoghlu Mosque in Beyshehir, Turkey. vacuum tubes. Such fragments do not help very much in recognizing the carpet-weaving characteristics of pre-Seljuk period (13th and 14th centuries AD) in Persia. What has remained from early times as evidence of carpet-weaving is nothing more than a few pieces of worn-out rugs. Therefore archaeologists are not able to make any particularly useful discoveries during archaeological excavations, save for special circumstances.

With the passage of time, the materials used in carpets, including wool and cotton, decay. . The majority of these carpets are wool, but several silk examples produced in Kashan survive. Still, some show figures engaged either in the hunt or feasting scenes.

This is because Islam, the dominant religion in that part of the world, forbids their depiction. Common motifs include scrolling vine networks, arabesques, palmettes, cloud bands, medallions, and overlapping geometric compartments rather than animals and humans. There is much variety among classical Persian carpets of the 16th and 17th century. However, painted depictions prove a longer history of production.

The earliest surviving corpus of Persian carpets come from the Safavid dynasty (1501-1736) in the 16th century. Carpet-weaving is undoubtedly one of the most distinguished manifestations of Persian culture and art, and dates back to the Bronze Age. The Persian rug is an essential part of Persian (Iranian) art and culture.

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