Noble gases Group

In contrast, the halogens and noble gases on the right of this block are distinctly nonmetallic. The noble gases, Group 18 of the periodic table, are monatomic gases that resist chemical attack because their electron configurations contain completely filled s and p orbitals. 

Noble gases (group 18 elements) have no color or odor and exist as individual gas atoms that experience London forces. These... 

The maximum oxidation number of any atom in any of its compounds is equal to its periodic group number, with a few exceptions. The coinage metals have the following maximum oxidation numbers Cu, +2 Ag, +2 and Au, +3. Some of the noble gases (group 0) have positive oxidation numbers. Some lanthanide and actinide element oxidation numbers exceed 3, their nominal group number. 

There seems to be something special about having eight valence electrons (often called an octet of electrons). For example, the noble gases (group 8A) have an octet of electrons (except for helium, which has only two electrons total), and they are so stable that they rarely form chemical bonds with other atoms. 

The noble gases (group 18 elements) are nonmetals and are exceptions to the diagonal rule. Noble gases are nearly chemically inert. The heavier noble gases form a number of compounds with oxygen and fluorine such as KrF2 and XeC>4... 

Fig. 5.25 The trend in the values of the first ionization energies of the noble gases (group 18).

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