Symbol | Ne |
Atomnummer | 10 |
Gruppe | 18 (Ædelgasser) |
Periode | 2 |
Blok | p |
Klassifikation | Ædelgasser |
Udseende | Colorless gas exhibiting an orange-red glow when placed in a high voltage electric field |
Farve | Farveløs |
Antal protoner | 10 p+ |
Antal neutroner | 10 n0 |
Antal elektroner | 10 e- |
Fase ved STP | Gas |
Massefylde | 0.9002 g/cm3 |
Atommasse | 20.1797 u |
Smeltepunkt | 24.56 K -248.59 °C -415.462 °F |
Kogepunkt | 27.104 K -246.046 °C -410.8828 °F |
Fordampningsvarme | 1.77 kJ/mol |
Elektronegativitet (Pauling Scale) | - |
Elektronaffinitet | -116 kJ/mol |
Oxidationstrin | 0 |
Ioniseringsenergier |
|
Forudsigelse | William Ramsay (1897) |
Opdagelse og første isolation | William Ramsay, Morris Travers (1898) |
Opdagelse af neon Neon was discovered in 1898 by the British chemists Sir William Ramsay (1852–1916) and Morris Travers (1872–1961) in London. Neon was discovered when Ramsay chilled a sample of air until it became a liquid, then warmed the liquid and captured the gases as they boiled off. The gases nitrogen, oxygen, and argon had been identified, but the remaining gases were isolated in roughly their order of abundance, in a six-week period beginning at the end of May 1898. First to be identified was krypton. The next, after krypton had been removed, was a gas which gave a brilliant red light under spectroscopic discharge. This gas, identified in June, was named "neon", the Greek analogue of the Latin novum ('new') suggested by Ramsay's son. The characteristic brilliant red-orange color emitted by gaseous neon when excited electrically was noted immediately. Travers later wrote: "the blaze of crimson light from the tube told its own story and was a sight to dwell upon and never forget." |