Orbital diagram writing

From each partial (valence-level) orbital diagram, write the ground-state electron configuration and group number ... 

EXAMPLE 8.2 Writing Orbital Diagrams Write the orbital diagram for sulfur and determine the number of unpaired electrons. SOLUTION ... 

Strategy Start with the electron configuration, obtained as in Section 6.5. Then write the orbital diagram, recalling the number of orbitals per sublevel, putting two electrons of opposed spin in each orbital within a completed sublevel, and applying Hund s rule where sublevels are partially filled. 

According to this model, a covalent bond consists of a pair of electrons of opposed spin within an orbital. For example, a hydrogen atom forms a covalent bond by accepting an electron from another atom to complete its Is orbital. Using orbital diagrams, we could write... 

We write the orbital diagram of each element following Hund s rule and count the number of unpaired electrons. 

We begin by writing the Lewis structure. The H atoms are terminal atoms. There are three central atoms and (3 x 1) + 4 + 6 + 4 + (3 x 1) = 20 valence electrons, or 10 pairs. A plausible Lewis structure is drawn at right. Each central atom is surrounded by four electron pairs, requiring sp3 hybridization. The valence-shell orbital diagrams for the atoms follow. 

Write the electron configurations of following species and draw their orbital diagrams. 

Use the aufbau principle to write complete electron configurations and complete orbital diagrams for atoms of the following elements sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, and argon (atomic numbers 11 through 18). 

For each of the elements below, use the aufbau principle to write the full and condensed electron configurations and draw partial orbital diagrams for the valence electrons of their atoms. You may consult the periodic table in Appendix C, or any other periodic table that omits electron configurations. 

In this section, you have seen how a theoretical idea, the quantum mechanical model of the atom, explains the experimentally determined structure of the periodic table, and the properties of its elements. Your understanding of the four quantum numbers enabled you to write electron configurations and draw orbital diagrams for atoms of the elements. You also learned how to read the periodic table to deduce the electron configuration of any element. 

Draw orbital diagrams and Lewis structures to show how the following pairs of elements can combine. In each case, write the chemical formula for the product. 

Write the electron configuration and draw an orbital diagram to show the first excited state of a sodium atom. Assume that the outermost electron is excited. 

Apply the Pauli exclusion principle, the aufbau principle, and Hund s rule to write electron configurations using orbital diagrams and electron configuration notation. 

A Suggested Procedure for Writing Molecular Orbital Diagrams... 

The following sample study sheet shows the general steps for writing complete electron configurations and orbital diagrams for uncharged atoms. 

Step 1 Write the complete electron configuration for the atom. (This step is not absolutely necessary, but it can help guide you to the correct orbital diagram.)... 

Writing Complete Electron Configurations and Orbital Diagrams for Uncharged Atoms... 

Write the complete electron configuration and draw an orbital diagram for antimony, Sb. 

Write electron configurations and orbital diagrams for the nonmetallic elements. (Section 11.2)... 

Write a complete electron configuration and an orbital diagram for each of the following. 

No more than two electrons can be placed in an orbital. If you are writing the electronic configuration using orbital diagrams (boxes representing the orbitals), two electrons in one orbital must have their spins paired, T 1. This is a requirement of the Pauli principle. 

Using boxes for the orbitals, write out the orbital diagrams for (a) nitrogen, (b) fluorine, and (c) vanadium. 

SAMPLE PROBLEM 8.1 Determining Quantum Numbers from Orbital Diagrams Problem Write a set of quantum numbers for the third electron and a set for the eighth electron of the F atom. 

FOLLOW-UP PROBLEM 8.1 Use the periodic table to identify the element with the electron configuration l5 25 /. Write its orbital diagram, and give the quantum numbers of its sixth electron. 

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