inert gases, also known as noble, is mainly engaged in the eighth subgroup of the periodic system.They number six helium (He), neon (Ne), argon (Ar), xenon (Xe) and radon (Rn).To understand the nature, first consider the concept of inertia.Inertia - a weak expression or lack of ability to react with other chemical elements.Cause a chemical reaction to form new links in such materials almost impossible.
Accordingly, an inert gas - a rare noble monatomic gas with a high inertia, which is due to energy sustainability outer electron shell of the atom level.For example, helium in this shell are two electron, and other noble gases - eight.This explains their physical and chemical properties.All inert gases under normal conditions of gases are colorless, odorless and poorly soluble in water.Their boiling points and melting points are increased according to increase of the size of atoms.
Until 1962, scientists were confident that all noble gases are completely inert.But a Canadian chemist N. Bartlett was able to prove the opposite, received the first chemical compound of xenon, the so-called geksaftoroplatinat xenon.This compound is an orange solid with a crystal lattice.In the future, a series of compounds has been greatly expanded.
prevalence and education in nature
In the universe of the noble gas helium is the most common, and in terrestrial conditions - argon (by volume it occupies 0.934%).In very small quantities of inert gases are in rocks of natural gas and combustible materials in dissolved form and can be found in oil and water.
Under natural conditions, the noble gases may be formed as a result of various nuclear reactions.For example, the source of radon are radioactive drugs uranium.Some of these chemicals is of cosmogenic origin.
all inert gases, in addition to Rawdon, have a number of isotopes.
Stocks of these gases are not reduced.Only helium slowly very slowly dissipated in interstellar space.
Application
Inert gases are widely used in electrical engineering.Argon, in view of the inactivity and low thermal conductivity, is used in a mixture with nitrogen for filling electric lamps.Filled with argon and neon tube light for advertisements, and they glow blue, and neon - orange-red.
more argon is used in chemical laboratories.In the industry it has found its application for the thermal treatment of easily oxidized metals.The argon provides a protective atmosphere in which you can weld or cut rare and non-ferrous metals, smelting of tungsten, titanium, zirconium.To control ventilation systems use a radioactive isotope of argon.
krypton and xenon have even lower thermal conductivity than argon, so filled with the electric lamps durability and efficiency than those filled with nitrogen or argon.
divers breathe a mixture of helium and oxygen, which can significantly extend their stay under the water and dramatically reduces the painful effects caused by the change in pressure during the ascent to the surface.
Liquid helium is used as refrigerant in various studies, since the boiling point of the gas is -268.9 ° C.
properties of complete inertia of the helium used for welding in its atmosphere, for the production of high-purity metals, chromatography.And it has created a high permeability leak detectors in the apparatus of low and high pressure.
