Talk:Rhodium

Template:Chemical Element

Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 12:23, 6 July 2005 by Femto (previous revision was that of 11:21, 24 May 2005).

Information Sources

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Rhodium. Additional text was taken directly from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table were obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but were reformatted and converted into SI units.

Talk

Added a comment about the sharp price decline of rhodium as a result of the global slowing economy.

---

Rhenium

Rhenium is not a precious metal. Am deleting the comment about it being so. —Preceding unsigned comment added by 69.27.245.170 (talk) 16:56, 27 August 2008 (UTC)[reply]

Does Rhodium in Jewlery items pause any danger of radiation? many white gold items from india have Rhodium in it and I am not sure if they are safe Please reply

Are you sure about the specific heat? I think you may be off by a factor of 1000.

The Rhodium page talks about reactivity with oxygen at length, or rather the lack thereof. Then in the table entry about Oxidation State, it talks about an amphoteric oxide. I suspect there is some algorithm generating this entry, as there is no means of editing it (that I see). I would like to see the mention of an oxide dropped with respect to the oxidation states available for Rhodium. Fortran (talk) 23:35, 3 January 2008 (UTC)[reply]

I found a factual error in the article. In the article it states that only small amounts of rhodium will dissolve in aquaregia. But if you bring the aquaregia to boiling temp It will dissolve both platinum and rhodium. I do this on a regular basis. As this is my bussiness.[user 69slinkys] 8:50 24 feb 2008 —Preceding unsigned comment added by 209.247.21.245 (talk) 15:52, 24 February 2008 (UTC)[reply]

It appears the Young's modulus and Bulk modulus values had been interchanged earlier, which I have now corrected. Poisson's ratio nu=0.26, and Young's modulus E=380 GPa are consistent with ASM Metals Handbook. Bulk modulus K = E/{3(1-2*nu)} shows that K must be less than E if nu is less than 1/3. This relation would give K=263 GPa.

Two other citations of sources reported on the web give K=275 GPa at 293.15K: K=275 GPa Darling, A.S. Journal of the Institute of Metals. 1966. K=274.5862 GPa, J.R.Handley. JM Internal document.

I have not checked the primary reference for these last two sources, but this is enough support to indicate that the earlier values for K,E had been interchanged. This error also occurred in another standard websource www.webelements.com and I have written to the editors of that source as well. Rbbwiki (talk) 23:55, 7 April 2008 (UTC) Rbbwiki (talk) 23:58, 7 April 2008 (UTC)[reply]

Unusual Property

Rhodium supposedly will not react with Fluorine, even though it will form compounds with Oxygen, Chlorine, etc.

Actually, rhodium does form RhF₃ and RhF₅, but only in the extremely forcing constraints of a pure fluorine atmosphere. These fluorides were synthesised.

Nuclear source

If significant amounts of rhodium occur in spent nuclear fuel, what is it a decay or fission product of? --Carnildo 05:27, 28 December 2005 (UTC)[reply]

According to the Chart of the Nuclides (14th Edition), the yield of mass number 103 from fission of U-235 is 3.03% from U-235, 1.57% from U-233, and 7.0% from Pu-239. Of course, Rh-103 is only 1 of many isotopes with a mass number of 103 which are produced. Rh-103 is the only stable isotope with a mass number of 103, so it will be the end product of beta minus decays from the neutron rich side and beta plus/electron capture decays from the neutron deficient side. Beta decay/electron capture is the only decay mechanism present, so all mass 103 produced by fission of U-233, U-235 or Pu-239 will result in Rh-103 eventually. The two longest lived isotopes at mass number 103 are Ru-103 (39.27d) on the neutron rich side and Pd-103 (16.99d) on the neutron deficient side. Fortran (talk) 23:30, 3 January 2008 (UTC)[reply]

biological activity and jewlery

The article says: "Compounds that contain rhodium are not often encountered by most people and should be considered to be highly toxic and carcinogenic. Rhodium compounds can stain human skin very strongly. This element plays no biological role in humans."

If that is really true, why is it used to plate jewlery? 71.199.123.24

-The article means COMPOUNDS, not the actual metal itself. the base metal is harmless but compounds such as rhodium (III) fluoride or rhodium (III) chloride

Borislav Dopudja 18:51, 2 July 2006 (UTC)[reply]

Elemetal rhodium is harmless, but his salts should be treated as a deadly poison.

Rhodium in 'Grills'

As many may know, Rhodium is used in plating jewelry. Among this jewelry, now commonly found to contain Rhodium, are Grills (dental jewelry most popular in hip hop fashion.)There has been talk of Rhodium making the wearers 'sick'; though no actual symptoms were specified. Perhaps more research should be done in this area.

Gold is also poisonous. [1] --Vuo 10:20, 16 July 2006 (UTC)[reply]

Gold may very well be toxic - the issue is that it's so inert that normally you're hard pushed to get any compounds formed in the first place. There are a handful that I've come across - lithium auride I think is one, along with LiAuCl and some others like the arthritis drug aurothioglucose. Oh. This is a discussion on Rhodium. Never mind. Dan Pope 00:42, 7 December 2006 (UTC)[reply]

Sources for Utah mining

According to the USGS, in their most recent platinum group mining summary, no Rhodium was mined in the United States -> [2]. Hipocrite - «Talk» 14:00, 26 May 2007 (UTC)[reply]

A source does not necessarily have current mining going on. Also, [3] says that US production is primarily platinum and palladium, but does not say entirely. --JWB 17:29, 26 May 2007 (UTC)[reply]

Well, certainly if someone can find a reliable source stating that there is substantial Rhodium in Utah, we could include it. Hipocrite - «Talk» 18:46, 26 May 2007 (UTC)[reply]

I have an unreliable source -- my bank account for WMG ventures since we take about 22 ounces a year of Rhodium out of there. There's also numerous reliable sources in the form of mining claims filed with the BLM office in SLC regarding platinum (Rhodium is a by product) mineral deposits in that area. Look for references of 1900's mining claims for "Gold Hill" in that area. Jeffrey Vernon Merkey 02:50, 28 May 2007 (UTC)[reply]

Recovery of Fission Rhodium

Can User:Cadmium please provide a source for the changes made regarding the radioactivity of fission rhodium? This article gives an activity of 1.3×10^-3 Ci/g after 5 years, which would be about 640 MBq for 13.3 grams, although this was apparently based on a different assumption about the half-life than the values given in Nubase. —Ta180 19:57, 14 June 2007 (UTC)[reply]

That article gives that figure per gram of ¹⁰²Rh, and says that isotope occurs only in trace quantities. --JWB 00:33, 15 June 2007 (UTC)[reply]

Well, yeah. Most fission products have a high number of neutrons and then undergo beta decay, but ¹⁰²Rh can not be formed in this way, as ¹⁰²Ru is stable. Formation of ¹⁰²Rh is an unlikely event, and as such only trace quantities are present. However this isotope and its nuclear isomer account for nearly all the radioactivity. The issue is that no sources were cited, and there's a 10x discrepency in these numbers.—Ta180 09:27, 15 June 2007 (UTC)[reply]

The point is that the article you cited gives a figure per gram of ¹⁰²Rh, and this Wikipedia article gives a figure for 13.3 grams of fission rhodium containing a small quantity of ¹⁰²Rh. It does not give any figure per gram of ¹⁰²Rh, though it can be computed. It states the initial proportion of ¹⁰²Rh in fission rhodium is 6.62×10⁻¹², and that the proportion surviving after 5 years is 4.7/67.1, or .464×10⁻¹² of fission rhodium, or 6.17×10⁻¹² gram per 13.3 grams. If the activity of this 6.17×10⁻¹² gram is 4.7 MBq, then the activity per gram is .762×10¹² MBq per gram.

Also, the article you cited gives a ratio of about 40 between the specific activities of ¹⁰²Rh and ^102mRh, while the ratio of halflives is 5 in the opposite direction. Does the decay energy really differ by a factor of 200?. --JWB 16:21, 15 June 2007 (UTC)[reply]

Becquerels and curies are units of decays per time, not decay energy. An activity of 1.3×10^-3 Ci/g for pure ¹⁰²Rh would correspond to a half-life of several million years, which makes no sense, so I assumed that this was referring to the total activity of the rhodium, and not just ¹⁰²Rh. I'm not arguing that the PMR paper is accurate, I am questioning the complete lack of sources in this article. —Ta180 01:11, 17 June 2007 (UTC)[reply]

Furnace Winding

What is a furnace winding in this context? —Preceding unsigned comment added by 209.169.125.74 (talk) 07:10, 9 July 2008 (UTC)[reply]

Acid

One part of the article said it was not attacked by acids, and slightly attacked by aqua regia. Later in the article there was an uncited statement saying that sulfuric acid completely dissolves rhodium. Aqua regia is far stronger than pure sulphuric acid, and can completely dissolve metals that sulphuric acid cannot even attack. 24.65.95.239 (talk) 01:25, 1 December 2008 (UTC)[reply]