Periodic table valence electron configurations

Most properties of metals, nonmetals, and metalloids are determined by their valence electron configurations. The number of valence electrons that a metal has varies with its position in the periodic table. Valence electrons in metal atoms tend to be loosely held. Nonmetals have four or more tightly held electrons, and metalloids have three to seven valence electrons. 

A primary goal of the periodic table is to assist recognition of the ground-state valence electron configuration of each atom, the chief determinant of its chemical properties" ([21], p 5). 

STRATEGY Determine the configuration of the neutral atom by referring to its position in the periodic table. Remove electrons from the valence-shell p-orbitals first, then... 

As in the discussion of hydrogen, in this section we examine the properties of the alkali metals in the context of the periodic table and focus on significant applications of the elements and selected compounds. The valence electron configuration of the alkali metals is s1, where n is the period number. Their physical and chemical properties are dominated by the ease with which the single valence electron can be removed (Table 14.3). 

Ion formation is only one pattern of chemical behavior. Many other chemical trends can be traced ultimately to valence electron configurations, but we need the description of chemical bonding that appears in Chapters 9 and 10 to explain such periodic properties. Nevertheless, we can relate important patterns in chemical behavior to the ability of some elements to form ions. One example is the subdivision of the periodic table into metals, nonmetals, and metalloids, first introduced in Chapter 1. 

The transition metals lie in the d block, at the center of the periodic table, between the s-block metals and the elements in the p block, as Figure 20-1 shows. As we describe in Chapter 8, most transition metal atoms in the gas phase have valence electron configurations of, where x is the group number of the metal. Titanium, for... 

Periodic table A chart that arranges the elements by atomic number in a way that the vertical columns produce groups of elements with similar valence electron configurations and chemical properties. 

It will pay you to know (without having to look in the periodic table or tables of electron configurations) that the halogens (F, Cl, Br, I, At) all have seven valence electrons, that the oxygen family (O, S, Se, Te) all have six, that the nitrogen family (N, P, As) have five, that the carbon family (C, Si) have four, and that the boron family (B) have three It will also pay you to know that electronegativities decrease from right to left in a row, or from top to bottom in a column, in the periodic table... 

The valence electron configuration of the atoms of the Group 2 elements is ms2, where n is the period number. The second ionization energy is low enough to be recovered from the increased lattice enthalpy (Fig. 14.22). Hence, the Group 2 elements occur with an oxidation number of +2, as the cation M2+, in all their compounds (Table 14.7). Apart from a tendency toward nonmetallic character in beryllium, the elements have all the chemical characteristics of metals, such as having basic oxides and hydroxides. 

Note in Fig. 12.26 that a very important pattern is developing The elements in the same group (vertical column of the periodic table) have the same valence electron configuration. Remember that Mendeleev originally placed the elements in groups based on similarities in chemical properties. Now we understand the reason behind these groupings. Elements with the same valence electron configuration often show similar chemical behavior. 

The entire periodic table is represented in Fig. 12.28 in terms of which orbitals are being filled. The valence electron configurations are given in Fig. 12.29 on page 555. 

The results considered in this section are very important. We have seen that the wave mechanical model can be used to explain the arrangement of elements in the periodic table. This model allows us to understand that the similar chemistry exhibited by the members of a given group arises from the fact that they all have the same valence electron configuration. Only the principal quantum number of the occupied orbitals changes in going down a particular group. 

Phosphorus and sulfur are neighboring elements in Period 3 of the periodic table and have the following valence electron configurations phosphorus is 3sz3p3, and sulfur is 3s23p4. 

The essence of the periodic table is that members of each group of representative elements exhibit similar chemical properties that change in a regular way. The quantum mechanical model has allowed us to understand that the similarity of properties of the atoms in a group arises from the identical valence electron configurations shared by group members. It is the number and type of valence electrons that primarily determine an atom s chemistry. 

Group (of the periodic table) a vertical column of elements having the same valence electron configuration and showing similar properties. (2.8)... 

The most appropriate position of hydrogen in the periodic table has been a matter of some dispute among chemists. Its electron configuration, Is is similar to the valence electron configurations of the alkali metals hence, hydrogen is most commonly... 

Given each of the following valence electron configurations, determine which block of the periodic table the element is in. 

Elements in the same group on the periodic table have similar chemical properties because they have the same valence electron configuration. 

Explain how an atom s valence electron configuration determines its place on the periodic table. (6.2)... 

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