Elemental Series 4
Non-Metals |
Alkali Metals |
Alkaline Earth Metals |
Transition Metals |
Poor Metals |
Metalloids |
Halogens |
Noble Gases |
The Lanthanides |
The Actinides
| Transition Metals |
| |
In chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings:
- It commonly refers to any element in the d-block of the periodic table, including zinc, cadmium and mercury. This corresponds to groups 3 to 12 on the periodic table.
- More strictly, IUPAC defines the transition metals as any element with an incomplete d subshell or that may form stable ions only with an incomplete d subshell (IUPAC definition). By this definition, zinc, cadmium, and mercury are excluded from the transition metals, as they have a d10 configuration. Only a few transient species of these elements that leave ions with a partly filled d subshell have been formed, and mercury(I) only occurs as Hg22+, which does not strictly form an lone ion with a partly filled subshell, and hence these three elements are inconsistent with the latter definition.[1] They do form ions with a 2+ oxidation state, but these retain the 4d10 configuration. Element 112 may also be excluded although its oxidation properties are unlikely to be observed due to its radioactive nature. This definition includes groups 3 to 11 on the periodic table.
The first definition is simple and has been traditionally used. However, many interesting properties of the transition elements as a group are the result of their partly filled subshells from d orbitals, a property which all members of the d-block except zinc, cadmium and mercury share. | |
21
Sc
44.9
| 22
Ti
47.88
| 23
V
50.94
| 24
Cr
52.00
| 25
Mn
54.94
| 26
Fe
55.85
| 27
Co
58.93
| 28
Ni
58.69
| 29
Cu
63.55
| 30
Zn
65.39
| 39
Y
88.91
| 40
Zr
91.22
| 41
Nb
92.91
| 42
Mo
95.94
| 43
Tc
(98)
| 44
Ru
101.1
| 45
Rh
102.9
| 46
Pd
106.4
| 47
Ag
107.9
| 48
Cd
112.4
| | | 72
Hf
178.5
| 73
Ta
180.9
| 74
W
183.9
| 75
Re
186.2
| 76
Os
190.2
| 77
Ir
192.2
| 78
Pt
195.1
| 79
Au
197.0
| 80
Hg
200.5
| | | 104
Rf
(261.1)
| 105
Db
(262)
| 106
Sg
(263)
| 107
Bh
(264)
| 108
Hs
(265)
| 109
Mt
(266)
| 110
Ds
(271)
| 111
Rg
(272)
| 112
Unu
(277)
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