Noble-gas anions

HeN , the only nitrogen-noble gas anion described, is predicted to be unbound. 

Whether an element is the source of the cation or anion in an ionic bond depends on several factors for which the periodic table can serve as a guide In forming ionic compounds elements at the left of the periodic table typically lose electrons giving a cation that has the same electron configuration as the nearest noble gas Loss of an elec tron from sodium for example yields Na which has the same electron configuration as neon... 

Elements at the right of the periodic table tend to gam electrons to reach the elec tron configuration of the next higher noble gas Adding an electron to chlorine for exam pie gives the anion Cl which has the same closed shell electron configuration as the noble gas argon... 

Transfer of an electron from a sodium atom to a chlorine atom yields a sodium cation and a chloride anion both of which have a noble gas electron configuration... 

As pointed out in Chapter 2, elements close to a noble gas in the periodic table form ions that have the same number of electrons as the noble-gas atom. This means that these ions have noble-gas electron configurations. Thus the three elements preceding neon (N, O, and F) and the three elements following neon (Na, Mg, and Al) all form ions with the neon configuration, is22s22p6. The three nonmetal atoms achieve this structure by gaining electrons to form anions ... 

Cations, anions, and atoms with ground state noble-gas electron cnnfigurations. Atoms and ions shown in the same color are isoelectronic tint. is. they have the same electron configiratiorts. 

Anion Species carrying a negative charge. Examples include Cl- and OH-, 38 noble gas, 38... 

Noble gas An element in group 18 at the far right of the periodic table, 31 anions, 38 cations, 38 characterization, 190 structures, 150-151... 

FIGURE 2.3 When nonmetal atoms acquire electrons and form anions, they do so until they have reached the electron configuration of the next noble gas. 

To predict the electron configuration of a monatomic cation, remove outermost electrons in the order np, ns, and (n — l)d fora monatomic anion, add electrons until the next noble-gas configuration has been reached. The transfer of electrons results in the formation of an octet (or duplet) of electrons in the valence shell on each of the atoms metals achieve an octet (or duplet) by electron loss and nonmetals achieve it by electron gain. 

L. Pauling, Proc. Roy. Soc., A114, 181 (1927). In this paper it was stated that the consideration of polarization of the anion by the cation would be expected to reduce the calculated values a number of facts, however, indicate that with ions with the noble gas structure the effect of polarization on the equilibrium distance is small. 

There are no noble gas partitioning data for amphiboles. Given the multiplicity of cation and anion sites in this mineral it seems likely that Uru will be higher than in other silicate minerals. 

Isoelectronic species must have the same number of electrons, and each element has a different atomic number, atoms of different elements cannot be isoelectronic. Two different cations may be isoelectronic, as may two different anions, or an anion and a cation. An example would be two anions (or two cations, or an anion and a cation) that have the electron configuration of a nearby noble gas, such as 02 and F", Na+ and Mg2+, or F and Na+. 

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