Noble gases are a group of chemical elements with similar properties. Six naturally occurring noble gases are helium, neon, argon, krypton, xenon and radioactive radon. As we saw before, helium was first discovered in 1868, while looking at the chromosphere of the Sun and was first isolated by William Ramsay.
Argon, the lazy one, was discovered by Lord Rayleigh and William Ramsay at University College, London in 1894. It was named so, due to its inert character. Krypton, neon, and xenon were discovered by William Ramsay in 1898. Radon was first identified in 1898 by Friedrich Ernst Dorn. However, it was not considered a noble gas until 1904 when its characteristics were found similar to other noble gases.
In 1904, Rayleigh and Ramsay received the Nobel Prizes in Physics and in Chemistry respectively for their discovery of the noble gases.
As these gases occur in smaller amounts in the atmosphere, they are also called rare gases. Helium is found sealed within some of the radioactive minerals and can be released on heating. Others are obtained by fractional distillation of liquid air.
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