Talk:Transition metal
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[edit] Shielding and Gold
While the article states: "The number of oxidation states of each ion increases up to Mn, after which they decrease. Later transition metals have a stronger attraction between protons and electrons (since there are more of each present), which then would require more energy to remove the electrons."
Would it not be more proper, this being a chemistry article and all, to invoke the concept of shielding, instead of beating around the bush.
Secondly, I was wondering should a discussion be done about golds aberrant yellow color. Which I have the understanding (from undergrad inorganic) is due to the 5d contraction as a result of relativistic mass coming into play. --PedroDaGr8 00:33, 22 April 2007 (UTC)
[edit] Ca3+
"In fact Ca3+ has an ionisation enthalpy so high that it rarely occurs naturally."
Are you sure? I never, ever heard of naturally occurring Ca3+! Sounds suspicious to me... --malbi
- I suspect this is true that it never occurs naturally. I think this paragraph should be reworked; it's too much about calcium and group II and not enough about transition metals. Olin
- I went and revised it. Olin
[edit] inconsistency
There seems to be an inconsistency in this article: Not all d block elements are transition metals. Scandium and zinc don't qualify..., yet both scandium and zinc are listed in the table at the top of the article, and shown as transition elements in the periodic table. Scandium is stated to be a transition element in its article, zinc is not so described in the text but is in the infobox. Possibly the definition is not agreed by all authorities, or has changed recently? Andrewa 22:07, 17 Sep 2004 (UTC)
- Whatever the historical cause, it seems that there are now two commonly accepted definitions of transition element and transition liquids. Although I am not a chemist I have had a go at fixing the article. It may still not be entirely accurate, and is not perfectly phrased, but I am confident that it is both better phrased and more accurate than what I started out with. Andrewa 14:07, 26 Jan 2005 (UTC)
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- I corrected this to the best of my knowledge. From looking at books and on the web, I still think 99% of all chemists consider scandium to be a transition metal. Hence, I referenced the IUPAC definition, which would discludes cadmium. I also did some general cleanup; the article still, however, clearly needs help. Olin
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- The reason that some dont consider it a transition metal is because it actually fills up the 4s electron orbital rather than the 3d. Notice the exception for copper can chromium in the chart on Electron_configuration. All4One 19:32, 8 October 2006 (UTC)
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[edit] From PNA/Chemistry
- Transition metal - I raised some issues with this article on its talk page some months ago and got no response. I have now rewritten the introduction to be consistent with the usage of the term elsewhere in Wikipedia, notably in the periodic table and in the articles on the transition elements themselves. But I'm relying on high school chemistry, many years ago. In view of the technical nature of some of the material and the very significant changes I have made just to the introduction, I think the whole article needs a review by someone more knowledgable. I was going to list it for peer review but the function of that page is now linked to featured articles, and so now there doesn't seem to be better a place than this to request the old sort of peer review, which is what is needed. Andrewa 03:16, 27 Jan 2005 (UTC)
[edit] four periods
I'm concerned at one change I have made. Previous text (emphasis mine):
This name comes from their position in the periodic table of elements, which represent the successive addition of electrons to the d atomic orbitals of the atoms as one progresses through each of the three periods.
My version (again, emphasis added):
The name transition comes from their position in the periodic table of elements. In each of the four periods in which they occur, these elements represent the successive addition of electrons to the d atomic orbitals of the atoms.
I'm not sure what was meant by three periods. Did it mean the three following periods, making four in all? Or was it just a mistake, and if so why am I the first to notice it? Or is there something I have misunderstood? Andrewa 20:35, 26 Jan 2005 (UTC)
- This has now been explained to me. Four is the correct number (whew), the probable reason for the earlier version saying three is that all transition elements in the fourth period in which transition elements occur are radioactive, with all their isotopes having sufficiently short half-lives that exploring their chemistry is a bit problematic, my informant actually said most do not have any substantial chemistry but I suspect some of my old AAEC collegues would disagree here, they regarded positronium as having substantial chemistry and were exploring it on the big (to us) Van de Graaff.
- The upshot is, while there were traditionally three periods of transition metals, now four are recognised... and there seems to be a consensus on that much, anyway. Andrewa 19:12, 17 July 2005 (UTC)
[edit] table of elements
I recommend that the table showing the transition metals be rearranged into horizontal periods and vertical groups like they would appear on the periodic table. I don't have enough wiki experience to try it for myself to see how it would look. If there is a good reason why the table is like this, I would at least like to know why. 164.58.8.58 17:42, 1 Mar 2005 (UTC)
- No idea why the original author put it there, but it seems to me that a flipped table would squeeze out most of the running text. YMMV. --Christopher Thomas 19:43, 16 May 2005 (UTC)
Yes, the flipped table is too wide to run on the right side, but seems short enough to give its own space to. So I've changed:
| Group | Period 4 | Period 5 | Period 6 | Period 7 | ||
|---|---|---|---|---|---|---|
| 3 (III B) | Sc 21 | Y 39 | Lu 71 | Lr 103 | ||
| 4 (IV B) | Ti 22 | Zr 40 | Hf 72 | Rf 104 | ||
| 5 (V B) | V 23 | Nb 41 | Ta 73 | Db 105 | ||
| 6 (VI B) | Cr 24 | Mo 42 | W 74 | Sg 106 | ||
| 7 (VII B) | Mn 25 | Tc 43 | Re 75 | Bh 107 | ||
| 8 (VIII B) | Fe 26 | Ru 44 | Os 76 | Hs 108 | ||
| 9 (VIII B) | Co 27 | Rh 45 | Ir 77 | Mt 109 | ||
| 10 (VIII B) | Ni 28 | Pd 46 | Pt 78 | Ds 110 | ||
| 11 (I B) | Cu 29 | Ag 47 | Au 79 | Rg 111 | ||
| 12 (II B) | Zn 30 | Cd 48 | Hg 80 | Uub 112 |
to:
| Group | 3 (III B) | 4 (IV B) | 5 (V B) | 6 (VI B) | 7 (VII B) | 8 (VIII B) | 9 (VIII B) | 10 (VIII B) | 11 (I B) | 12 (II B) |
|---|---|---|---|---|---|---|---|---|---|---|
| Period 4 | Sc 21 | Ti 22 | V 23 | Cr 24 | Mn 25 | Fe 26 | Co 27 | Ni 28 | Cu 29 | Zn 30 |
| Period 5 | Y 39 | Zr 40 | Nb 41 | Mo 42 | Tc 43 | Ru 44 | Rh 45 | Pd 46 | Ag 47 | Cd 48 |
| Period 6 | Lu 71 | Hf 72 | Ta 73 | W 74 | Re 75 | Os 76 | Ir 77 | Pt 78 | Au 79 | Hg 80 |
| Period 7 | Lr 103 | Rf 104 | Db 105 | Sg 106 | Bh 107 | Hs 108 | Mt 109 | Ds 110 | Rg 111 | Uub 112 |
Please leave a message on my talk page if you want any additional formatting changes. -- Rachel 20:42, 15 August 2005 (UTC)
[edit] why there is only 8 groups in periodic table and not more?
I want to know why the outermost shell of atom only have at most 8 electrons?But the previous shell can have 18,32...?
- Because a new shell is always started after 8 electrons even if there is room for more electrons to go in; the partly filled shell is completed later. (note this is only true for atoms, not ions) Physchim62 (talk) 15:03, 19 November 2005 (UTC)
why a new shell is always started after 8 electrons?
- Because, for an atom (not for an ion), the nd sub-shell is higher in energy than the (n+1)s sub-shell. Physchim62 (talk) 08:02, 20 November 2005 (UTC)
what is the difference between ion and atom?
- An atom has the same number of electrons as protons, and so has no electrical charge. An ion has more or fewer electons than protons, and so has an electrical charge. The energies of the different shells depends on the number of protons and on the number of electrons—the enrgies are different for each element, but the order is roughly the same. Physchim62 (talk) 08:12, 20 November 2005 (UTC)
[edit] is ion stable?
are ions sable since they have gained or lost electrons?
- Please sign your posts on talk pages, even if not logged in. Andrewa 08:50, 4 February 2006 (UTC)
[edit] Definition (again), zinc, scandium and now cadmium
See Wikipedia talk:WikiProject Chemistry#Transition metals. Andrewa 08:50, 4 February 2006 (UTC)
[edit] A user's comment
A user with IP address 207.160.218.253 put the following comment into the article itself. I removed it from the article, but it sounded well-meaning rather than intentional vandalism, so I'm copying it here. The comment said: "Transition metals change all the time. They just change from one metal to another. You can get a peice of gold and can get platinum or any of the transition metals. It has a cool rippleing effect." NOTE: I (user elysdir) know nothing at all about the topic nor about this particular comment, so please don't ask me about it. I'm simply moving another user's comment from the article body to the Talk page. --Elysdir 17:39, 30 November 2006 (UTC)
[edit] iron(V)
Iron in the picture is listed as having a common +5 oxidation state. I don't think that's right. I think it's absolutely extremely rare. Olin 19:32, 17 April 2007 (UTC)
- The image is wrong in numerous other points as well. Someone give me a ping when I get back to France in a couple of days and I will get the data together for a corrected version. Physchim62 (talk) 21:25, 17 April 2007 (UTC)
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- I suggest using the figure from chapter 2 of Greenwood, which is more comprehensive as it also includes negative oxidation states. The current figure is unsourced, which makes me wonder who decided which oxidation states should be included as "common" and "less common". --Itub 12:05, 15 October 2007 (UTC)
[edit] Are noble metals also transition metals?
I saw the definition here to be: "More strictly, IUPAC defines a transition metal as an element whose atom has an incomplete d sub-shell". This is supposed to exclude zinc, cadmium and mercury and leave groups 3 to 11 in the definition. The noble metals (copper, silver and gold) however have also a filled d-shell (according to webelements.com). Why are they called transition metals as well then? Erwin 15:34, 3 September 2007 (UTC)
[edit] Are you serious?
Are you serious? You don't have a picture of a periodic table displaying which metals are the transition metals? I have to read to figure it out? How can you be serious? —Preceding unsigned comment added by 69.134.171.127 (talk) 02:00, 14 February 2008 (UTC)
[edit] Conductivity
It would be nice to get some general trend as to the conductivity of transition metals. Someone knowledgeable on this subject please add this into the main article. Thanks. Gautam Discuss 22:56, 15 May 2008 (UTC)
