Electronic configuration table

We have already observed (in Exercise 21-2) that the alkaline earths have similar chemistry. As shown in Table 21-1, they have similar electron configurations. Table 21-111 shows that each element has two valence electrons. With these basic likenesses in mind we shall explore the chemical trends among these elements. 

Make an electron configuration table like Table 22-1 for the fifth-row transition elements— yttrium (Z = 39) through cadmium (Z = 48). In elements 41 through 45, one of the 5s electrons moves over to a 4d orbital. In element 46, two electrons do this. 

Group 13/III is the first group of the p block. Its members have an ns np1 electron configuration (Table 14.5), and so we expect a maximum oxidation number of +3. The oxidation numbers of B and A1 are +3 in almost all their compounds. However, the heavier elements in the group are more likely to keep their s-electrons (the inert-pair effect, Section 1.19) so the oxidation number +1 becomes increasingly important down the group, and thallium(I) compounds are as common as... 

Zinc, Cu and Ni have similar ionic radii and electron configurations (Table 5.6). Due to the similarity of the ionic radii of these three metals with Fe and Mg, Zn, Cu and Ni are capable of isomorphous substitution of Fe2+ and Mg2+ in the layer silicates. Due to differences in the electronegativity, however, isomorphous substitution of Cu2+ in silicates may be limited by the greater Pauling electronegativity of Cu2+ (2.0), whereas Zn2+ (1.6) and Ni2+ (1.8) are relatively more readily substituted for Fe2+ (1.8) or Mg2+ (1.3) (McBride, 1981). The three metals also readily coprecipitate with and form solid solutions in iron oxides (Lindsay, 1979 Table 5.7). 

Atomic Electron Configuration Table. http //www.en.wikipedia.org/wiki/Atomic electron configuration table (accessed November 2, 2005). 

Although most of the complex chemistry is concentrated in the triva-lent oxidation state of the rare earth ions, it is possible to ionize the rare earths by successive removal of electrons. We have earlier tabulated the ground state electronic configurations (Table 6 and 10) of the rare earth atoms and trivalent ions, and those of the mono- and divalent (M+, M2+) ions1 are given below. In this chapter we shall concern our-... 

Consequently all the halogens occur as halides. All these elements belong to the same group 17 of the periodic table which is indicated by the observed gradation in properties of these elements as is expected from their electronic configuration (Table). 

The most extensive group of complexes that are known to have this oxidation state are the mixed halide-phosphine derivatives of the triply bonded Re4+ core, a moiety that possesses the electron-rich o2n 52S 2 electronic configuration (Table 2).5... 

Early in the actinide series, electrons in the 6d orbitals are lower in energy than there is 5f orbitals, This is clear from the ground-state electronic configurations (Table 9.3) of the atoms, which show that the 6d orbitals are filled before 5f. The 5f orbitals are starting to be filled at protoactinium, and with the exception of curium, the fid orbitals are not occupied again. 

Next, let us consider the formation of the fluorine molecule, F2, from two fluorine atoms. As we can see from our table of electronic configurations (Table 1.1), a fluorine atom has two electrons in the s orbital, two electrons in the 2 orbital, and two electrons in each of two 2p orbitals. In the third Ip orbital there is a single electron which is unpaired and available for bond formation. Overlap of this p orbital with a similar p orbital of another fluorine atom permits electrons to pair and the bond to form (Fig. 1.4). The electronic charge is concentrated between the two nuclei, so that the back lobe of each of the overlapping orbitals... 

You may be surprised to learn that carbon forms four covalent bonds since you know that carbon has only two unpaired electrons in its ground-state electronic configuration (Table 1.2). But if carbon were to form only two covalent bonds, it would not complete its octet. Now we need to come up with an explanation that accounts for carbon s forming four covalent bonds. 

Manganese group olefin compounds have electronic configuration (Table 6.14). Cationic complexes such as [Mn(CO)5 (olefin)] are not formed from the unstable Mn(CO)g but from the chlorocarbonyl compound Mn(CO)5Cl and olefin in the presence of AICI3, or by protonation reaction of <7-allyl compounds ... 

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