The inert gases in the periodic table are elements of the main subgroup of group VIII: helium, neon, argon, krypton, xenon and radon, the latter being a radioactive element.
They are also called noble gases.
Electronic structure of inert gases
All inert gases have a complete, stableThe configuration of the external electronic level: helium is a doublet, the remaining gases have an octet. Each of them completes the corresponding period in the periodic table.
Inert gases in nature
All inert gases, except radioactive radon,Can be found in the composition of atmospheric air. Helium is the most common element in space after hydrogen. The sun is 10% composed of this noble gas, formed from hydrogen by the reaction of nuclear fusion with the release of positrons and antineutrinos.
Physical properties of noble gases
The inert gases are represented by monatomicMolecules. Under normal conditions, helium, neon, argon, krypton and xenon - gases without color and odor, poorly soluble in water. The larger their atomic number, the higher the boiling point and melting point.
Helium has unique properties: It remains liquid even at the lowest temperatures, down to absolute zero, without undergoing crystallization. Crystallization of helium is possible only at a pressure of 25 atmospheres. In addition, this gas has the lowest boiling point of all substances.
Chemical properties of noble gases
For a long time it was believed that inert gases in generalDo not form connections. However, experimentally under special conditions, fluorides and xenon oxides were obtained, the existence of which was predicted by the theoretician Linus Pauling.
How inert gases are used
Thanks to its outstanding physico-chemicalProperties of inert gases are widely used in science and technology. So, with the help of liquid helium, ultra-low temperatures are obtained, and a mixture of helium and oxygen in a ratio of 4: 1 is used as an artificial atmosphere for the breathing of divers.
Since helium is the lightest gas after hydrogen, it is often filled with airships, probes and balloons. Its lifting force is 93% of the lift force of hydrogen.
Neon, argon, krypton and xenon are used inLighting equipment - production of gas-discharge tubes. When electric current is passed through tubes filled with neon or argon, the gas begins to glow, and the color of this radiation depends on the gas pressure.
Argon as the cheapest of noble gases is used to create an inert atmosphere in the conduct of chemical reactions, whose products interact with oxygen.