f-block

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Periodic Table 2.svg

The f-block of the periodic table of the elements consists of those elements whose atoms or ions have valence electrons in f-orbitals. Actual electronic configurations may be slightly different from what is predicted by the Aufbau principle. The elements are also known as inner transition elements, although that term is normally taken to include lutetium and lawrencium as well, which are part of the d-block.[not verified in body]

f-block in the periodic table
Electron configurations excluding s-electrons
Lanthanides 57
La
58
Ce
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
Atomic electron configuration 5d1 4f15d1 4f3 4f4 4f5 4f6 4f7 4f75d1 4f9 4f10 4f11 4f12 4f13 4f14
Electrons per shell 2, 8,
18,
18, 9,
2
2, 8,
18,
19, 9,
2
2, 8,
18,
21, 8,
2
2, 8,
18,
22, 8,
2
2, 8,
18,
23, 8,
2
2, 8,
18,
24, 8,
2
2, 8,
18,
25, 8,
2
2, 8,
18,
25, 9,
2
2, 8,
18,
27, 8,
2
2, 8,
18,
28, 8,
2
2, 8,
18,
29, 8,
2
2, 8,
18,
30, 8,
2
2, 8,
18,
31, 8,
2
2, 8,
18,
32, 8,
2
** Actinides 89
Ac
90
Th
91
Pa
92
U
93
Np
94
Pu
95
Am
96
Cm
97
Bk
98
Cf
99
Es
100
Fm
101
Md
102
No
Atomic electron configuration 6d1 6d2 5f26d1
or
5f16d2
5f36d1 5f46d1
or
5f5
5f6 5f7 5f76d1 5f9
or
5f86d1
5f10 5f11 5f12 5f13 5f14
Electrons per shell 2, 8,
18, 32,
18, 9,
2
2, 8,
18, 32,
18, 10,
2
2, 8,
18, 32,
20, 9,
2
2, 8,
18, 32,
21, 9,
2
2, 8,
18, 32,
22, 9,
2
2, 8,
18, 32,
24, 8,
2
2, 8,
18, 32,
25, 8,
2
2, 8,
18, 32,
25, 9,
2
2, 8,
18, 32,
27, 8,
2
2, 8,
18, 32,
28, 8,
2
2, 8,
18, 32,
29, 8,
2
2, 8,
18, 32,
30, 8,
2
2, 8,
18, 32,
31, 8,
2
2, 8,
18, 32,
32, 8,
2

All elements in the lanthanide series form M3+ ions. In aqueous solution the early lanthanides are surrounded by nine water molecules while the later lanthanides have a coordination number of 8. Cerium also forms compounds with the +4 oxidation state; Ce4+ has the very stable electronic configuration of the noble gas xenon and is a strong oxidising agent. Eu2+ has the configuration [Xe]4f7 and is a strong reducing agent. The existence of Eu(II) is attributed to the stability of the half-filled f-shell.[1]

See also[edit]

References[edit]

  1. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419.  Chapters 30 and 31

External links[edit]