Periodic table diagonal line

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. 

The periodic table displays the pattern of properties of the elements. The lightest are at the top of the chart the atomic weights increase toward the bottom of the chart. The elements to the upper right, above a diagonal line from aluminum (13) to polonium (84), are nonmetals, about half of... 

The Periodic Table of the Elements.—In Table XXI-1 we list the elements in order of their atomic numbers, which are given in addition to their symbols. The atoms in the table are arranged in rows and columns in such a way as to exhibit their periodic properties. The diagonal lines are drawn in such a way as to connect atoms of similar... 

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. 

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. 

In Section 3.5, we classified elements as metals, nonmetals, or metalloids. The heavy stair-step line beginning at boron and running diagonally down the periodic table separates the elements into metals and nonmetals. Metals are usually lustrous, malleable, and good conductors of heat and electricity. Nonmetals are just the opposite—nonlustrous, brittle, and poor conductors. Metalloids are found bordering the heavy diagonal line and may have properties of both metals and nonmetals. 

Without referring to your text, predict the trend of second ionization energies for the elements sodium through argon. Compare your answer with Table 7.5. Explain any differences. 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. 

If you are ever required to list the sublevels in order of increasing energy without reference to a periodic table, the following diagram taken from the summary of the quantum model may be helpful. Beginning at the upper left, the diagonal lines pass through the sublevels in the sequence required. 

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. 

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