Historical Timeline: Noble Gas Chemistry
| Year | Event | Significance |
|---|---|---|
| 1894 | Argon discovered by Lord Rayleigh and William Ramsay | First noble gas isolated; called "lazy" element (from Greek "argos" = idle) |
| 1895 | Helium isolated on Earth by William Ramsay | Previously known only in sun (spectroscopy) |
| 1898 | Krypton, Neon, Xenon discovered by Ramsay and Travers | Discovery of 3 noble gases in one year by fractional distillation of liquid air |
| 1900-1960 | Noble gases considered completely inert | Dogma: complete outer shell = zero chemistry possible |
| 1962 | Neil Bartlett synthesizes XePtF6 | First noble gas compound! Revolutionized chemistry — proved noble gases can form bonds |
| 1962 | XeF4 and XeF2 synthesized | Rapid expansion of xenon chemistry following Bartlett's discovery |
| 1963 | XeF6 synthesized | Highest fluoride of xenon; sp3d3 hybridization; distorted octahedral |
| 1964 | XeO3 (explosive) characterized | Hydrolysis product of XeF6; demonstrated xenon oxide chemistry |
| Modern | Xe used in ion engines, anesthesia, medical imaging | Noble gas chemistry has practical applications today |
NEET relevance: Historical facts about xenon compounds are rarely tested, but knowing that Bartlett discovered XePtF6 in 1962 as the "first noble gas compound" is a useful fact for assertion-reason questions.