The Inert Gases Group

Electron configuration ls2 Atomic number 2 Ionisation potential (eV) 24.5 2s22p 10 21.5 3s23p 18 15.7 4s24p8 36 13.9 6s25p 64 12.1 6s26p 86 10.7 

Ions with the inert gas configuration are easily formed from the alkali metals, and those of the halogens are also stable. The ionisation potential for 

Interaction between inert gas atoms is slight, the Van der Waals forces being due entirely to dispersion interaction (p. 116). Liquefaction is therefore difficult the elements have much lower b.p. than compounds of about the 

The liquefaction of helium by a controlled expansion process necessitates preliminary cooling because its Joule-Thomson coefficient is negative (spontaneous expansion heats the gas) down to an inversion temperature of 40 All the gases have C /C ratios very close to 5/3, the theoretical value for an ideal monatomic gas. The elements are liquid over very small temperature ranges. Plelium can be solidified only under pressure under 26 atmospheres it solidifies at 0.9 °K. 

When helium is cooled to 2.18 °K at 1 atmosphere (the A-point), a remarkable liquid, helium II, is obtained. It has  

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The inert gases (Group 18) are represented by isotopes of Kr and Xe. These isotopes are generally short-lived and will decay before fuel reprocessing. As inert gases, they are unreactive and consequently they are isolated using cryogenic techniques. 

The halogens are a family of elements appearing on the right side of the periodic table, in the column just before the inert gases. The elements in this group—fluorine, chlorine, bromine, iodine, and astatine—show some remarkable similarities and some interesting trends in chemical behavior. The similarities are expected since the... 

As a consequence of this [satisfactory placing of the inert gases in a zero group preceding group I]. .. we can. . . expect elements of a zero series with atomic weights much smaller than that of hydrogen. 

According to this definition the group of bases practically includes just about the same substances as the Br0nsted conception, but with a few additions such as the inert gases (e.g. argon reacts as a base with boron trifluoride). On the other hand, the category of acids is much wider than... 

In the original scheme, in addition to a detailed account of the elements of Group O, the general principles of Inorganic and Physical Chemistry were discussed in Volume I. It was later felt, however, that this arrangement was hardly satisfactory, and an Introduction to these principles is now afforded by my Text-book of Physical Chemistry, Volumes I. and II. (1982-85), whilst in future editions the first volume of this Series will deal with the Inert Gases alone. 

The group in the Periodic Table with the least complicated chemistry is almost certainly the alkali-metal group lithium (Z — 3), sodium (Z 11), potassium (Z = 19), rubidium (Z 37), cesium (Z = 55), and the recently discovered francium (Z = 87). These elements follow directly after the inert gases and thus have one single valence electron beyond a well-shielded nucleus. 

The Inert Gases.—The study of the solubility of the gases of group 0 of the Periodic Table has proved very interesting. The data published by Antropoff3 are given in the following table ... 

The Group 18 elements in the periodic table are currently called the noble gases. In the past, however, they were referred to as the inert gases. They were believed to be totally unreactive. Scientists have found that this is not true. Some of them can be made to react with reactive elements, such as fluorine, under the proper conditions. In 1962, the synthesis of the first compound that contained a noble gas was reported. Since then, a number of noble gas compounds have been prepared, mostly from xenon. A few compounds of krypton, radon, and argon have also been prepared. 

Helium is a member of the noble gas family. The noble gases are the elements in Group 18 (VIIIA) of the periodic table. The periodic table is a chart that shows how the elements are related to one another. The noble gases are also called the inert gases. Inert means that an element is not very active. It will not combine with other elements or compounds. In fact, no compounds of helium have ever been made. 

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