Talk:Palladium

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Contents

[edit] Telecommunications uses

Hi, in the "Applications" section, the bullet point "Telecommunications switching-system equipment uses palladium." seemed a little vague. (It made me wonder where, how and why it was used.) So I googled around a bit and came up with some more specific uses. I hope that's allright. I couldn't find anything specific to telecomm switches though... please provide more specific info if you have any. Infinoid 17:55, 19 August 2006 (UTC)

Palladium was/is used in the contact points of relays to reduce pitting caused by electrical arcs which occur when the relay contact is opened while the circuit is under power. Pd alloyed contacts are used in some motor starter relays. The information with regard to telecommunication switching systems is no longer vaild in the US as these systems no longer use relays using instead solid-state components [computers]. Drrocket 15:02, 3 January 2007 (UTC)

[edit] Conflicting info

The article says this at one point: "Palladium is one of the two metals which can be alloyed with gold to produce White gold. (Nickel can also be used.)"

Which conflicts with the page on White Gold which claims that it can be made by Gold alloyed with Silver as well.

I would think that it should be changed to indicate that Palladium is one of many or that Pd, Ni and Ag are the most commonly used. Pt, Pd, Ir, Rh and Ni all work well to de-colorize Gold. Never tried Os or Ru so I could not say if they will do so... Drrocket 01:54, 24 November 2006 (UTC)

[edit] Featured Article?

I've cleaned up the references and external links, converting the ext links to citations. I also cleaned up the list and turned it into prose. Perhaps we can find the remaining citations and then submit it for peer review, then FAC? --Rifleman 82 20:20, 4 February 2007 (UTC)

[edit] Clathrate

Under the Characteristics heading the following statement is present:


It is thought that this possibly forms palladium hydride (PdH2) but it is not yet clear if this is a true chemical compound.


I find the above statement unsatisfactory - if it can not be defined more precise e.g.:


It is thought that this possibly forms palladium hydride (PdH2) or a clathrate. However, it is not yet clear exactly what chemical entity is formed.


then the statement should be deleted.


This are some references to hydrogen and palladium compounds, but non of them mentiones the PdH2 as something special.--Stone 10:33, 12 February 2007 (UTC)


[edit] 107Ag 107Pd

  • J. H. Chen, G. J. Wasserburg (1990). "The isotopic composition of Ag in meteorites and the presence of 107Pd in protoplanets". Geochimica et Cosmochimica Acta 54 (6): 1729-1743. doi:10.1016/0016-7037(90)90404-9. 

This review like article could be used as source, but I have to read it first.--Stone 10:46, 12 February 2007 (UTC)

This might be the original report from 1978.

  • Kelly, W.R. and Wasserburg, G.J. (1978). "Evidence for the existence of 107Pd in the early solar system". Geophys. Res. Lett. 5: 1079–1082. 

--Stone 10:50, 12 February 2007 (UTC)

[edit] Photography

[1] this is a howto for palladium photography.--Stone 09:18, 15 February 2007 (UTC)

[edit] Electron Shells

Does anyone know how palladium has an empty outer shell while the second in shell contains 18 electrons.Sk8tuhpunk 03:07, 25 March 2007 (UTC)

It has something to do with the s, p, d, and f orbitals, how it's easier for it to have an empty valence shell and 18 in the next to last shell. 204.16.224.110 21:31, 13 October 2007 (UTC)

Yes, see Electron_shells#Exceptions_in_3d.2C_4d.2C_5d --JWB 08:45, 14 October 2007 (UTC)

[edit] Free vs alloyed

The first sentence of the second paragraph currently reads: "Palladium is usually found as a free metal, alloyed with others in the platinum group." I'm not a chemist, but... isn't "free" contradictory with "alloyed?" If not, could someone add some wikilinks to clarify the meanings of these words? Thanks. — Epastore 03:04, 5 May 2007 (UTC)

It must mean not in a compound such as an oxide, as most less inert metals are found in nature. --JWB 08:43, 14 October 2007 (UTC)

[edit] Art section not related to palladium processing

I am not sure why the "Art" section is linked to the stub for palladium processing. Palladium processing is a photographic technique, whereas the Art section discusses manuscript illumination. You do not use the same techniques to apply palladium to paper for manuscript illumination as you do for photography purposes. The techniques employed are wholly unrelated. If anything, the link ought to be to the Illuminated_manuscript page. I believe the link should be altered or at least removed from the Art section, but I am reluctant to do so as I am very new to the Wikipedia editing process. Yakityak (talk) 10:17, 13 April 2008 (UTC)

[edit] ISO currency codes

I've restored the information I added once before regarding the ISO currency codes of palladium bullion. IMO it's an interesting and encyclopedic fact, and belongs in this article. A schoolchild researching palladium for a project, for example, would probably not think to check the ISO 4217 article without this paragraph. I don't know why it was removed; If you remove it again, please give some reason here. The articles on the other three ISO currency code bullion metals give their codes. Andrewa (talk) 14:28, 8 May 2008 (UTC)