Neon is a
chemical element with symbol
Ne and
atomic number 10. It is in
group 18 (noble gases) of the
periodic table. 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 is derived from the Greek word,
νέον, neuter singular form of
νέος [
neos], meaning new. Neon is chemically
inert and forms no uncharged chemical compounds.