The chemistry of noble gases
Noble gases are truly a very interesting group of elements, that all have relatively similar properties. The chemical side of of these compounds is very similar. Under standard conditions (under temperature of 0°C, and pressure of 100 kPa) they are all colorless and odorless monoatomic gases with a very low chemical activity. The six noble gases that appear in the nature are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn) which is radioactive and mostly comes only in traces.
The mentioned elements form the last group (group 18) of the periodic table of elements. The reason why noble gases are so stable lies in their electron structure. Their outer shell of valence electrons is considered to be full, what gives them very little or no reason to take a part in chemical reactions and form new compounds. However, a few compounds have been prepared, mostly with the element xenon.
Neon, argon, krypton and xenon can be obtained from air, by using the method of liquefaction of gases and the process of fractional distillation. Radon is mostly isolated from the radioactive decay of radium compounds.
Noble gases have many interesting applications. From welding and lighting, to space exploration. A mixture of helium and oxygen is often used by deep-sea divers so that they can avoid negative effects of nitrogen and oxygen under high pressure (like oxygen toxemia and nitrogen narcosis), that can cause serious problems, or even death. Helium is often used as a gas in blimps and balloons since, with time, people realized that the use of hydrogen (which is flammable, and potentially explosive if mixed with oxygen) is very dangerous. Liquid helium is often used as a coolant in many systems that require low temperatures. Almost all noble gases are also used as filling gases for various types of light bulbs, because of their lack of chemical activity. Use in neon tubes is also known in which different gases produce different colors. Helium produces a bright and slightly red color, neon produces an intensively red color, argon produces a blue color, krypton a slightly pink color, and xenon produces violet coloration.
Noble gases also have many other interesting applications. If one is interested in finding out more about the chemistry of these interesting elements, it’s always a good idea to start with some of the essential chemistry related tutorials.