Periodic table metal-nonmetal line

Explain, in terms of electronegativities, why the dividing line between metals and nonmetals in the periodic table (the red line that steps down from beneath B to between Po and At) is oriented the way that it is (as opposed to being, for example, horizontal or vertical). 

Diagonal relationships are commonly observed between elements from the second and third series. This periodic trend is especially true for the following pairs of elements Li/Mg, Be/AI, and B/Si. While vertical periodic trends are still predominant, some properties match better along a diagonal. These diagonal periodic trends are no doubt related to the fact that the radius of an atom increases down and to the left in the periodic table, whereas I.E. and E.A increase up and to the right The diagonal nature of the metal-nonmetal line has already been discussed. 

On the periodic table, metals are located on the left of the heavy zigzag line, and nonmetals are to the right of the heavy zigzag line. 

The metal-nonmetal line is the fifth component of our network of interconnected ideas for understanding the periodic table. It is summarized in Figure 9.19, which shows both the diagonal stepwise line in the periodic table and the metalloid elements along that line. A color version of Figure 9.19 is shown inside the front cover of the book. In our future discussions, the metal-nonmetal line component of the network will be represented by the icon shown at left. It symbolically represents this jagged line that separates the metals from the nonmetals. 

To make sense out of the descriptive chemistry of the representative elements, we have defined and discussed the basis of the first five components of a network of interconnected ideas for understanding the periodic table. These organizing principles are (1) the periodic law, (2) the uniqueness principle, (3) the diagonal effect, (4) the inert-pair effect, and (5) the metal-nonmetal line. The definitions of these components are summarized in Table 9.5. The five components are also summarized in Figure 9.20. A color version of this figure is shown on the inside front cover of the text. 

Mastering the descriptive chemistry of the main-group or representative elements of the periodic table is a formidable task. In order to bring some order to our study of this topic, we have started to construct a network of interconnected ideas. Five components have been described in this chapter. Three additional components will be defined and described in the next few chapters. The first five components are the periodic law, the uniqueness principle, the diagonal effect, the inert-pair effect, and the metal-nonmetal line. 

The fourth network component, the inert-pair effect, states that the valence ns electrons of main-group metallic elements, particularly those to the right of the second- and third-row transition metals, are less reactive than expected. These relatively inert ns pairs mean that elements such as In, Tl, Sn, Pb, Sb, Bi, and Po often form compounds where the oxidation state is 2 less than the expected group valence. The two major reasons for this effect are (1) larger-than-normal effective nuclear charges in these elements and (2) lower bond energies in their compounds. The fifth network component, the metal-nonmetal line, is just the division of the periodic table into metal, nonmetal, and metalloid regions. 

Sketch the icon that represents the metal-nonmetal line. Briefly explain how the icon symbolically represents the fifth component of the interconnected network of ideas for understanding the periodic table. 

Figure 9.19 page 244 The metal-nonmetal line in the periodic table... 

Nonmetals lie on the upper right side of the periodic table. The dividing line between metals and nonmetals is the zigzag diagonal line running from boron to astatine. Nonmetals have varied properties—some are solids at room temperature, others are... 

Periodic table. The group numbers stand above the columns. The numbers at the left of the rows are the period numbers. The black line separates the metals from the nonmetals. [Note A complete periodic table is given inside the front cover.)... 

The diagonal line or stairway that starts to the left of boron in the periodic table (Figure 2.7, page 31) separates metals from nonmetals. The more than 80 elements to the left and below that line, shown in blue in the table, have the properties of metals in particular, they have high electrical conductivities. Elements above and to the right of the stairway are nonmetals (yellow) about 18 elements fit in that category. 

Along the stairway (zig-zag line) in the periodic table are several elements that are difficult to classify exclusively as metals or nonmetals. They have properties between those of elements in the two classes. In particular, their electrical conductivities are intermediate between those of metals and nonmetals. The six elements... 

This book uses the vertical structure for listing the elements in groups 13 through 18 between periods 2 and 5. Therefore, the elements included as metallics, metalloids, nonmetals, and so on are arranged in a different order (vertical) according to their atomic numbers rather than following the zigzag line on the periodic table. 

Where on the following outline of a periodic table does the dividing line between metals and nonmetals fall ... 

Find, label by name and outline the following families on your periodic table alkali metals, alkaline earth metals, transition metals, halogens, and inert gases. Draw a dark line to show the separation between metals and nonmetals. Also, draw lines to enclose the metalloids. Colored pencils can be used to distinguish between the families. 

Metals, nonmetals, and atomic radius Elements in the periodic table are divided into the two broad categories of metals and nonmetals with a jagged line separating the two as shown in the figure. 

Look at the periodic table. There is a darker stairstep line dividing it into right and left portions. The elements to the left of this line are called metals, whereas those to the right are called nonmetals, with the exception of the column of elements on the right-hand border of the table. These elements in the last column are neither metals nor non-metals but rather are called noble gases. Helium (He), the familiar gas used to fill up balloons, is the first of these noble gases. 

As expected, the elements of a given column in the periodic table all behave in the same way because they all have the same number of valence electrons. There are a few exceptions to this rule, as you can tell if you look at the stairstep line passing through the periodic table. The elements to the right of the stairstep behave as nonmetals, whereas the elements to the left of this line behave as metals. But overall, the generalizations and trends apparent from the periodic table make it invaluable as a predictive tool. 

Account for the fact that the line that separates the metals from the nonmetals on the periodic table is diagonal downward to the right instead of horizontal or vertical. 

The periodic table. The elements in the A groups are the representative elements. The elements shown in pink are called transition metals. The dark line approximately separates the nonmetals from the metals. The elements that have both metallic and nonmetallic properties (semimetals) are shaded in blue. 

Metalloids (semimetals) elements along the division line in the periodic table between metals and nonmetals. These elements exhibit both metallic and nonmetallic properties. (12.16 18.1)... 

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