Scandium electronic configurations

Except for the elements at the ends of the rows, each transition metal can exist in several different oxidation states. The oxidation states displayed by the 3d transition metals are shown in Table 20-1. The most important oxidation states are highlighted in the table. The most common oxidation state for the 3d transition metals is +2, known for all the elements except Sc. Chromium, iron, and cobalt are also stable in the +3 oxidation state, and for vanadium and manganese the -H4 oxidation state is stable. Elements from scandium to manganese have a particularly stable oxidation state corresponding to the loss of ah the valence electrons configuration). 

Suppose we want to write the electron configuration of scandium (atomic number 21). We can rewrite the first 12 electrons that we wrote above for magnesium, and then just keep going. As we added electrons, we filled the first shell of electrons first, then the second shell. When we are filling the third shell, we have to ask if the electrons with n = 3 and / = 2 will enter before the n = 4 and 1 = 0 electrons. Since (n + /) for the former is 5 and that for the latter is 4, we must add the two electrons with n = 4 and / = 0 before the last 10 electrons with n = 3 and / = 2. In this discussion, the values of m and s tell us how many electrons can have the same set of n and / values, but do not matter as to which come first. 

We note in the electron configuration for electrons 13 through 20 for scandium that when the (n +1) sum was 4 we added the 3p electrons before the 4s electrons. Each of these groups has an (n 4- /) sum of 4. Since the (n + /) values were the same, we added electrons having the lower n value first. 

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 table shows the electronic configuration in spectroscopic and orbital box notation for the elements from scandium to zinc. [Ar] represents the electronic configuration of argon, which is Is 2s 2p 3s 3p . It is okay to use this shorthand here instead of writing out the full electron shells up to 3p. However, in the exam you should write out the spectroscopic notation for each element in full. 

Scandium always forms Sc + ions and, because the 4s electrons are lost first, the electronic configuration of the Sc + ion is Is 2s 2p 3s 3p so there are no electrons in the d subshell. 

Group 3 of the Periodic Table consists of the elements scandium, yttrium and either lanthanum or lutetium, depending upon the preferred arrangement of the Table. Group 3 elements have the outer electronic configuration ns2 p, and invariably their solution chemistry is that of the + 3 state. In this text, treatment of both La and Lu is carried out in Chapter 8, which deals with the f-block elements. Lanthanum and lutetium represent the first and last members of the lanthanide series. 

There are other subtleties in electron configurations for the transition elements illustrated in Table S.3. For all the neutral atoms from scandium to zinc, the 4s orbitals are the most easily ionized, and are removed first in... 

A comparison of the volumes per formula unit for the trifluorides is more complicated than for the difluorides because of the changes in structure type. If these changes are ignored, then some correlation with electronic configuration is possible. For the first transition series the volume decreases from scandium to chromium, increases from chromium to iron, and decreases to cobalt. This is as expected for the characteristic ligand-field stabilization effects (49), comparable with those for the difluorides. In the second series, there is a decrease from... 

Transition elements. Elements of the first transition series are characterized by having incompletely filled 3d orbitals in one or more of their common oxidation states. The series includes scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel and copper, which have electronic configurations of the form (ls)2(2s)2(2p)6(3s)2(3p)6(3[Pg.41]

Lanthanide elements (referred to as Ln) have atomic numbers that range from 57 to 71. They are lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). With the inclusion of scandium (Sc) and yttrium (Y), which are in the same subgroup, this total of 17 elements are referred to as the rare earth elements (RE). They are similar in some aspects but very different in many others. Based on the electronic configuration of the rare earth elements, in this chapter we will discuss the lanthanide contraction phenomenon and the consequential effects on the chemical and physical properties of these elements. The coordination chemistry of lanthanide complexes containing small inorganic ligands is also briefly introduced here [1-5]. 

Electron configurations for potassium through krypton. The transition metals (scandium through zinc) have the general configuration [Ar]4s23dn, except for chromium and copper. 

You ve probably noticed that in everything we ve said so far about electronic configuration, bonding and formulae we ve missed out a big block of elements altogether. Those are the ones in the centre of the periodic table, starting with scandium in the top left and running to mercury in the bottom right. This block of elements is called the transition metals. What makes them special ... 

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