The following electron configurations represent excited states. Identify the element and write its ground-state condensed electron configuration.
(a) \(1 s^{2} 2 s^{2} 2 p^{4} 3 s^{1}\),
(b) \([\mathrm{Ar}] 4 s^{1} 3 d^{10} 4 p^{2} 5 p^{1}\),
(c) \([\mathrm{Kr}] 5 s^{2} 4 d^{2} 5 p^{1}\).
Text Transcription:
1s22s22p43s1
[Ar]4s13d104p25p1
[Kr]5s2 4d25p1
Step 1 of 5) The following electron configurations represent excited states. Identify the element and write its ground-state condensed electron configuration. AB5 can be thought of as a trigonal planar AB3 arrangement with two additional atoms, one above and one below the equilateral triangle. The octahedral shape for AB6 has all six B atoms at the same distance from atom A with 90° B¬A¬B angles between all neighboring B atoms. Its symmetric shape (and its name) is derived from the octahedron, with eight faces, all of which are equilateral triangles. You may have noticed that some of the shapes we have already discussed are not among the five shapes in Figure 9.3. For example, in Figure 9.2, neither the bent shape of the SO2 molecule nor the trigonal pyramidal shape of the NF3 molecule is among the shapes in Figure 9.3. However, as we soon will see, we can derive additional shapes, such as bent and trigonal pyramidal, by starting with one of our five basic arrangements. Starting with a tetrahedron, for example, we can remove atoms successively from the vertices, as shown in Figure 9.4. When an atom is removed from one vertex of a tetrahedron, the remaining AB3 fragment has a trigonal-pyramidal geometry. When a second atom is removed, the remaining AB2 fragment has a bent geometry.
