Elements, electron configurations of the

let us give some systematic examples to illustrate how electrons are placed in the orbitals. 

For the hydrogen atom (Z = 1) since the least possible energy level of jH Is1 

For the helium atom (Z = 2) the first electron of helium atom will be ye s2 distributed just like the single hydrogen electron, but the second [T 

For the lithium atom (Z = 3) since the Is2 orbital has already y Is2 2s1 been occupied by the first two electrons, the third electron is [f Iff 

The corresponding electron distributions of these elements are given below. 

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There is no single best form of the periodic table since the choice depends on the purpose for which the table is used. Some forms emphasize chemical relations and valence, whereas others stress the electronic configuration of the elements or the dependence of the periods on the shells and subshells of the atomic structure. The most convenient form for our purpose is the so-called long form with separate panels for the lanthanide and actinide elements (see inside front cover). There has been a lively debate during the past decade as to the best numbering system to be used for the individual... 

Write the symbol and the abbreviated electron configuration of the element described. 

When the electron configurations of the elements were worked out, it became clear that the valence electrons of the period 2 elements must be accommodated in just four orbitals, the 2s and the three 2p orbitals. In the localized orbital model it is assumed that each bond can be described by a localized orbital formed by the overlap of one orbital on each of the bonded atoms. According to this model, therefore, a period 2 element can form bonds with at most four ligands so that electron configurations appeared to provide a justification for the octet rule. 

Paramagnetism indicates unpaired electrons, which in turn are often associated with partially filled subshells. First we write the electron configurations of the elements, and then those of the ions. From those electron configurations, we determine whether the species is paramagnetic or diamagnetic. 

Table Al.l Electronic configuration of the elements. Elements in square brackets (e.g., [He]) imply that the electronic configurations of the inner orbitals are identical to those of the element in brackets. Thus silver (Ag, atomic number 47) has a configuration of [Kr]4(7105 1, which if written out in full would be s22s22p62s22p62d1QAs1Ap6Adw5>s1, giving 47 electrons in all. For the heavier elements (atomic number above 55), the alternative notation K, L, M is used to denote the inner shells corresponding to orbitals 1, 2 and 3 respectively. This notation is common in X-ray spectroscopy (see p. 33). (Adapted from Lide, 1990.)...

The Periodic Table can be subdivided into four blocks (s, p, d and f)- These blocks correspond to the outer electronic configurations of the elements within these blocks. 

When we consider the electronic configurations of the elements from scandium to zinc, we are usually filling the 3d subshell according to the aufbau principle. Once again, the electronic configuration has to fit in with the electron arrangement given in the SQA Data Booklet. 

The chemical properties of atoms and the types of bond they form with each other are determined by their electron shells. The electron configurations of the elements are therefore also shown in Fig. A. Fig. B explains the symbols and abbreviations used. More de-... 

The quantum mechanical model and the electron configurations of the elements provide the basis for explaining many aspects of chemistry. Particularly important are the electrons in the outermost orbital of... 

Figure 1.3 The Periodic Table showing the atomic numbers and outer electronic configurations of the elements the core configurations are those of the preceding Group 18 element those that are numbered, but unnamed, have been synthesized in small quantities...

This procedure may be continued, one electron at a time, until the entire list of dements has been covered. A complete list of electron configurations of the elements... 

The experimentally determined ground-state electron configurations of the elements are shown in Figure 5.17. 

The physical and chemical properties of the elements are directly related to their electron configurations. For example, chemical properties such as gaining, giving and sharing of electrons are dependent on the valence electrons and nucleus structure. As a result, chemical behaviors of the elements are closely related to the nucleus structure and electron configuration of the element. Elements in the same period contain different numbers of electrons in the valence shells. 

The valence electron configurations of the elements in the same group are the same. Therefore, elements in the same group show similar chemical behaviors in a chemical reaction, but their physical properties may gradually change. 

The electron configuration of the element which is placed in the 3rd period and group 4A is ls22s22p63s23p2. Therefore, the number of electrons is 14. 

Write down the ground state electron configuration of the element 47Ag. ... 

Write the electron configuration of the element fitting each of the following descriptions. Use noble-gas notations. 

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