What is Neon atom?

   

  Neon is a chemical element with the symbol Ne and atomic number 10.  It is a noble gas.  Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air.  It was discovered (along with krypton and xenon) in 1898 as one of the three residual rare inert elements remaining in dry air, after nitrogen, oxygen, argon and carbon dioxide were removed.  Neon was the second of these three rare gases to be discovered and was immediately recognized as a new element from its bright red emission spectrum.  

     The name neon singular form of (neos), meaning new.  Neon is chemically inert, and no uncharged neon compounds are known.  The compounds of neon currently known include iconic molecules, molecules held together by VAN DER WALLS forces and clathrates.  During cosmic nucleogenesis of the element large amounts of neon are built up from the alpha-capture fusion process in stars.  Although neon is a very common element in the universe and solar system ( it is fifth in cosmic abundance after hydrogen, helium, oxygen and carbon,) it is rare on Earth.

     It composes about 18.2 ppm of air by volume (this is about the same as the molecular or mole fraction) and a smaller fraction in Earth's crust.  The reason for neon's relative scarcity on Earth and the inner planets is that neon is highly volatile and forms no compounds to fix it to solids.  Even the outer atmosphere of Jupiter is somewhat depleted of neon, although for a different reason.  Neon is used in some plasma tube and refrigerant applications but has few other commercial uses.  It is commercially extracted by the fractional distillation of liquid air.  Since air is the only source, it is considerably more expensive than helium.