'Noble gases' is the most common designation for the elements in the rightmost group (group 0, group VIII or group 18 depending on which nomenclature is being used) of The Periodic Table of the Elements. The commonly found designations 'inert gases' or 'rare gases' are somewhat misleading. First, they are not inert in a strict sense. And second, they are not rare. Argon for example makes up almost 1% of the atmosphere, and Helium is the second most common element in the entire known universe.

For a number of complicated reasons, which involve serious Quantum Mechanics, and electron filling rules for atomic Shells and Orbitals, these elements have many properties in common. One of them is their extremely low chemical reactivity. For example, one cannot burn noble gases, one cannot do normal chemistry with them. This extremely low reactivity is also the reason why these elements are called 'noble': in analogy to the 'noble' and very un-reactive precious metals - or because of their arrogant behaviour: seen from a chemical perspective these elements will not get together with other elements, just like some 'noble' aristocrats. Some pieces of data on the noble gases are collected in the following table:

Noble Gases: Yesterday and Today

One consequence of the aforementioned noble gases' low reactivity was that these Elements were discovered and isolated only realtively late. The first person to actually isolate and note the presence of 'noble gases' - however without going into further details - was Henry Cavendish (1731-1810 chemistry weirdo and 'discoverer' of hydrogen) in 1785. The real 'discovery' of the noble gases, their isolation and proper characterison took place between 1890 and 1900. A key figure in the process of discovering, isolating and characterizing the noble gases was a chap called Ramsay, who in the end went 'Nobel' for the noble stuff (more details are in The History Around the Noble Gases).

All noble gases are widely used in industrial applications and in scientific research. Except for radon they are all used as luminescent gases, e.g. in Lasers or in Neon Lighting. They are also widely used as protective gases e.g. in semiconductor manufacturing. Except for helium and radon all gases are obtained from the fractioned distillation of liquid air. Helium is not held in the atmosphere by the earth's gravity. However, helium (originating from radioactive decay) is found sealed or trapped deep inside the earth, commonly along with gas and petroleum, from where it is extracted. Helium is the most well-known and most widely used 'noble gas', e.g. to fill baloons and dirigibles. Radon is very difficult to obtain as a pure gas, since it is not a stable element. Even so, it has found use as a radioactive tracer gas for medical applications in the past.

For a long time it was thought that the noble gases are unable to perform any chemical reaction and form a compound. It has been questioned whether this is absolutely true. In the 1960s the first noble-gas compound was synthesized using a very tough oxidizer (platinum hexafluoride) and xenon; the compound, a yellow solid, is xenon hexaflouroplatinate (XePtF₆^-). A few other noble-gas compounds were synthesised after that, however they do not find any broad application and are mainly of academic interest.