Ionization energy, 167 periodic table

Nonmetals follow the general trends of atomic radii, ionization energy, and electron affinity. Radii increase to the left in any row and down any column on the periodic table. Ionization energies and electron affinities increase up any column and towards the right in any row on the periodic table. The noble gases do not have electron affinity values. Ionization energies are not very important for the nonmetals because they normally form anions. Variations appear whenever the nonmetal has a half-filled or filled subshell of electrons. The electronegativity... 

As you move across a period, or row, to the right in the periodic table, ionization energy increases ( Figure 9.35 on the next page). 

As you move down a colunm in the periodic table, ionization energy decreases, making electrons more likely to be lost in chemical reactions. Consequently ... 

Atomic structure Quantum theory Atomic orbitals Electronic configurations Periodic table Ionization energies Electron affinities... 

It should make sense that the farther an electron is from an atom s nucleus, the less the electrostatic force of attraction will be between that electron and the nucleus with its positively charged protons. In addition, in the case of atoms with many electrons, the inner electrons—the electrons that are located in shells that are closer to the nucleus—will tend to at least partially shield electrons that are farther away from the nucleus so that they do not feel the full positive charge of the nucleus. The result is that as the size of atoms increases, their ionization energy decreases. Since the size of atoms increases descending a column of the periodic table, ionization energy decreases descending a column. 

Figure 6.21 I The graph shows the first ionization energy (in kj/mol) vs. atomic number for the first 38 elements in the periodic table. The inset in the upper right emphasizes the general periodic trend Ionization energy increases from left to right and bottom to top in the periodic table.

Although the Periodic Trends Ionization Energy movie (eChapter 7.4) depicts clear trends in the magnitudes of first ionization energies, the movie shows that the trend from left to right across the periodic table is not smooth. 

Information on ionization energies, solubiUties, diffusion coefficients, and soHd—Hquid distribution coefficients is available for many impurities from nearly all columns of the Periodic Table (86). Extrinsic Ge and Si have been used almost exclusively for infrared detector appHcations. Of the impurities,... 

The electron configuration or orbital diagram of an atom of an element can be deduced from its position in the periodic table. Beyond that, position in the table can be used to predict (Section 6.8) the relative sizes of atoms and ions (atomic radius, ionic radius) and the relative tendencies of atoms to give up or acquire electrons (ionization energy, electronegativity). 

In this section we will consider how the periodic table can be used to correlate properties on an atomic scale. In particular, we will see how atomic radius, ionic radius, ionization energy, and electronegativity vary horizontally and vertically in the periodic table. 

Consider the fluorides of the second-row elements. There is a continuous change in ionic character of the bonds fluorine forms with the elements F, O, N, C, B, Be, and Li. The ionic character increases as the difference in ionization energies increases (see Table 16-11). This ionic character results in an electric dipole in each bond. The molecular dipole will be determined by the sum of the dipoles of all of the bonds, taking into account the geometry of the molecule. Since the properties of the molecule are strongly influenced by the molecular dipole, we shall investigate how it is determined by the molecular architecture and the ionic character of the individual bonds. For this study we shall begin at the left side of the periodic table. 

The location of the metals in the periodic table is shown in Figure 17-4. We see that the metals are located on the left side of the table, while the nonmetals are exclusively in the upper right corner. Furthermore, the elements on the left side of the table have relatively low ionization energies. We shall see that the low ionization energies of the metallic elements aid in explaining many of the features of metallic behavior. 

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