Network of ideas

The network of ideas presented in this section defines what we will henceforth denote as the Induced Deexcitation (ID) model. Note that this is neither a model... 

CHAPTER 9 Building a Network of Ideas to Make Sense of the Periodic Table... 

One of the most attractive aspects of the science of chemistry is the way it all fits together. Typically, students first learn the basics of atomic and molecular structure add some knowledge of thermodynamics, kinetics, and equilibrium and then quickly start to apply these ideas to more advanced topics. For example, you may have already studied Chapters 2 through 6 of this book and seen how the ideas that you worked so hard to master in your previous chemistry experiences provide the basis for the study of coordination compounds. Or, perhaps you have read Chapters 7 and 8 on the structures and energetics of solid-state chemistry. Alternatively, you may have skipped directly from Chapter 1 to this point to start a study of the chemistry of the periodic table and the representative elements. In any case, no matter in what order you have started to make your way through the discipline we call chemistry, the ultimate goal is the development of an interconnected network of ideas that you can use to rationalize and predict a variety of chemical behavior. Nowhere is such a network more essential than in a study of what has become known as descriptive chemistry, the properties, structures, reactions, and applications of the elements and their most important compounds. 

Icons for the first five components of the interconnected network of ideas for understanding the periodic table. These components are introduced here in Chapter 9. 

The periodic law. A summary of the general vertical and horizontal periodic trends in effective nuclear charge (4,), atomic radii (r), ionization energies (IE), electron affinities (EA), and electronegativities (EN). A color version of this figure is also available inside the front cover. The existence of the color versions are indicated by icons like that shown below. The periodic law is the first component of the interconnected network of ideas for understanding the periodic table. 

Of chlorine, oxygen, fluorine, and neon, which has the highest (that is, the most negative) electron affinity Briefly but carefully explain your answer in terms of two of the components of the interconnected network of ideas to make sense of the periodic table. As part of your answer, calculate the effective nuclear charges that operate on electrons being added to fluorine, oxygen, and neon. 

There are two known chlorides of lead lead(II) chloride, PbCl2, and lead(IV) chloride, PbCl4. Briefly rationalize the existence of these two compounds on the basis of the interconnected network of ideas for understanding the periodic table. Which of these would you suspect would be more saltUke— that is, which compound would have the greater ionic character Briefly rationaUze your answer in terms of another component of the network. 

In Chapter 9 we started to develop a network of ideas to make sense of the periodic table. The five components developed at that time were (1) the periodic law (trends in effective nuclear charge, radii, ionization energy, electron affinity, and electronegativity). 

THE ACID-BASE CHARACTER OF OXIDES AND HYDROXIDES IN AQUEOUS SOLUTION THE SIXTH COMPONENT OF THE INTERCONNECTED NETWORK OF IDEAS FOR UNDERSTANDING THE PERIODIC TABLE... 

Figure 9.20 presented a summary of the five components of the interconnected network of ideas developed in Chapter 9 to begin to make sense of the periodic table. It was presented in black-and-white on page 246 and in color on the front inside cover of the text. The acid-base character of oxides and hydroxides in aqueous solution is of central-enough importance that it now becomes the sixth component of the network. We will represent it with the icon shown at left. 

Our network of ideas can be applied to oxides, which divide into metal ionic and nonmetal covalent types. Ionic oxides are basic anhydrides that produce metal hydroxides and hydroxide ions in aqueous solution. Nonmetal oxides are acidic anhydrides that produce oxoacids and hydronium ions in solution. These correlations have become the sixth component of our network of ideas. The relative strengths of oxoacids and hydroacids can be rationalized by using other parts of the network. A systematic approach to the nomenclature of the oxoacids is based on the five representative -ic acids. 

In Chapter 9 we established the first five components of our interconnected network of ideas for understanding the periodic table. These included the periodic law, the uniqueness principle, the diagonal effect, the inert-pair effect, and the metal-nonmetal line. These components are summarized individually and collectively in colored figures located on the front inside cover of the book The icons for each component are shown there as well as on the bookmark pullout in the back of the text. In Chapter 10 we discussed hydrogen and the hydrides (as well as basic nuclear processes). In Chapter 11 we discussed the chemistry of oxygen, reviewed and extended our knowledge of the nature of water and aqueous solutions, and added a sixth component to our network the acid-base character of oxides and their corresponding hydroxides and oxoacids. The network with this additional component is shown in color on the top left side of the back inside cover of the book. 

The alkali metals superimposed on the interconnected network of ideas. These include the periodic law,... 

The seven components of the interconnected network of ideas. Trends in standard reduction potentials join the periodic law, the uniqueness principle, the diagonal effect, the inert-pair effect, the metal-nonmetal line, and the acid-base character of the metal (M) and nonmetal (NM) oxides in aqueous solution. 

Based on the network of ideas, rationalize the trends in radii, ionization energies, electron affinities, and electronegativities of the Group 2A elements. 

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