History of the discovery of xenon begins in 1785. Scientist Henry Cavendish investigated the composition of the air and, when passed through a discharge, he came to a curious fact: after the removal of nitrogen monoxide and excess oxygen, about 1 / 120 the original volume remained, and in any compound does not enter. He suggested that the atmosphere contains some other unknown gas. Descriptions of these particular experiments, and read William Ramsay. Especially going into this problem it is not become, but drew attention (I must say that by the end of the 19th century the atmospheric composition was considered fully investigated and the presence of new elements in it seem absurd). After a while, start a new allocation of gas from the air air it pushed a John Raleigh. This English physicist involved in determining the densities of the main gases in the atmosphere of our planet.
He suddenly discovered that the weight of 1 liter of nitrogen obtained by chemical means – 1, 2505 grams, and isolated from the air – 1, 2572 of a gram. It turned out that the nitrogen in the atmosphere heavier than at 0, 0067 gram. It became clear that the air is still unknown gas. Ramsay, along with William Morris Traverso (1872-1961) began work in search of gas. These two British scientists have made a real feat never before had scientists working with so many of the source material, look for gas in very small quantities, but even to the same and do not enter into chemical reaction. The search was performed by liquefying air and its subsequent evaporation – different gases evaporate at different temperatures.
With the help of spectral analysis reveals that the gas was obtained. As a result, processed About 100 tons of air, scientists have a microscopic portion of the gas volume of 0, 2 cm3. Had been "caught" neon ("new"), krypton ("hidden") and xenon ("alien"). Ramsay suggested calling the group of gases "rare", but historically more name stuck inert. All this happened in 1898. At first it seemed that these gases do not react with any elements. Only in the early 1960s. it turned out that the idea of the inert gases as chemical 'corpses' is untenable. Managed to get fluorides, oxides and other compounds of xenon (xenon), krypton, radon and later. Only for light noble gases the possible formation of any stable compounds are excluded.