Difference between revisions of "Rhodium" - New World Encyclopedia

Vapor pressure
45	ruthenium ← rhodium → palladium
	periodic table
General
Name, Symbol, Number	rhodium, Rh, 45
Chemical series	transition metals
Group, Period, Block	9, 5, d
Appearance	silvery white metallic ;
Atomic mass	102.90550(2) g/mol
Electron configuration	[Kr] 4d8 5s1
Electrons per shell	2, 8, 18, 16, 1
Physical properties
Phase	solid
Density (near r.t.)	12.41 g/cm³
Liquid density at m.p.	10.7 g/cm³
Melting point	2237 K; (1964 °C, 3567 °F)
Boiling point	3968 K; (3695 °C, 6683 °F)
Heat of fusion	26.59 kJ/mol
Heat of vaporization	494 kJ/mol
Heat capacity	(25 °C) 24.98 J/(mol·K)
Atomic properties
Crystal structure	cubic face centered
Oxidation states	2, 3, 4; (amphoteric oxide)
Electronegativity	2.28 (Pauling scale)
Ionization energies	1st: 719.7 kJ/mol
	2nd: 1740 kJ/mol
	3rd: 2997 kJ/mol
Atomic radius	135 pm
Atomic radius (calc.)	173 pm
Covalent radius	135 pm
Miscellaneous
Magnetic ordering	no data
Electrical resistivity	(0 °C) 43.3 nΩ·m
Thermal conductivity	(300 K) 150 W/(m·K)
Thermal expansion	(25 °C) 8.2 µm/(m·K)
Speed of sound (thin rod)	(20 °C) 4700 m/s
Speed of sound (thin rod)	(r.t.) 275 m/s
Shear modulus	150 GPa
Bulk modulus	380 GPa
Poisson ratio	0.26
Mohs hardness	6.0
Vickers hardness	1246 MPa
Brinell hardness	1100 MPa
CAS registry number	7440-16-6
Notable isotopes

Latest revision as of 20:04, 8 December 2022

Rhodium (chemical symbol Rh, atomic number 45) is a rare, silvery-white, inert metal. It is a member of the platinum group of elements and is found in platinum ores. As the most expensive precious metal,^[1] it is a symbol of wealth and is occasionally used in the presentation of high honors.

This metal is a hardening agent for the production of durable, heat-resistant alloys with platinum and palladium. These alloys can be found in such items as furnace windings, thermocouple elements, aircraft spark plugs, and laboratory crucibles. Rhodium is also good for making electrical contacts, and it is a valuable catalyst for automobile catalytic converters and various industrial processes. As a highly reflective metal, it provides a good finish for jewelry, mirrors, and searchlights.

Occurrence

Rhodium occurs in small amounts in ores of other metals such as platinum, palladium, nickel, silver, and gold. Its industrial extraction and purification processes are therefore complex. Principal sources of this element are located in South Africa, Russia (river sands of the Ural Mountains), and some parts of North and South America. In Canada, it is extracted from the copper-nickel sulfide mining area of the Sudbury, Ontario region. Although the quantity at Sudbury is very small, the large amount of nickel ore processed makes rhodium recovery cost-effective. The main exporter of rhodium is South Africa, followed by Russia.

Rhodium can also be extracted from spent nuclear fuel, which contains an average of 400 grams of rhodium per metric ton. Rhodium from this source contains radioactive isotopes with half-lives of up to 2.9 years. In other words, after every 2.9 years, the radioactivity drops by 50 percent. It is therefore stored for at least 20 years in a secure area, to allow it to become stable.

Discovery

Rhodium (Greek rhodon, meaning "rose") was discovered in 1803 by William Hyde Wollaston, soon after he discovered palladium. Wollaston made this discovery in England using crude platinum ore that presumably came from South America. After performing a series of chemical reactions to extract platinum and palladium from the ore, he obtained a red powder of sodium rhodium chloride (Na₃RhCl₆.12H₂O). He then isolated rhodium metal from the powder by reacting it with hydrogen gas.

Notable characteristics

Rhodium foil and wire

Rhodium is classified as a transition metal. In the periodic table, it lies in period five between ruthenium and palladium and is closely related to the latter two elements. In addition, it is situated in group nine (former group 8B), between cobalt and iridium.

This hard, silvery metal is highly reflective and extremely resistant to corrosion. It has a higher melting point and lower density than platinum. It is not attacked by most acids and dissolves only in aqua regia (a mixture of concentrated hydrochloric acid and nitric acid in the ratio 3:1 by volume). If slowly cooled from a red-hot state in the presence of air, rhodium changes to the sesquioxide, and the latter converts back to the metal at higher temperatures.

Isotopes

Naturally occurring rhodium is composed of only one isotope, ¹⁰³Rh, which is stable. In addition, many radioactive isotopes, ranging in mass numbers from 89 to 122, have been produced artificially. Of these, the radioisotopes with the longest half-lives are: ¹⁰¹Rh, with a half-life of 3.3 years; ¹⁰²Rh, with a half-life of 2.9 years; ^102mRh, with a half-life of 207 days; and ⁹⁹Rh, with a half-life of 16.1 days.

Applications

The primary use of rhodium is as an alloying agent for hardening platinum and palladium. These alloys are used in furnace windings, bushings for glass fiber production, thermocouple elements, aircraft turbine engines and spark plugs, and laboratory crucibles.
Rhodium is also used as an electrical contact material due to its low electrical resistance, low and stable contact resistance, and its high corrosion resistance.
Plated rhodium, made by electroplating or evaporation, is extremely hard and is used for optical instruments.
Given its highly reflective nature, this metal is used as a finish for jewelry, decorative items, mirrors, and search lights.
Rhodium is an important catalyst in automobile catalytic converters and a number of industrial processes (such as the manufacture of acetic acid from methanol). It also catalyzes a process (addition of hydrosilanes to a double bond) used for the manufacture of certain silicone rubbers.
The complex of a rhodium ion with the organic compound called “BINAP” gives a widely used catalyst for certain organic chemical syntheses.

Chlorides of rhodium

The name rhodium(III) chloride usually refers to hydrated rhodium trichloride, a molecular compound with the formula RhCl₃(H₂O)₃. Another prominent rhodium chloride is RhCl₃, a polymeric solid that behaves quite differently. Most chemistry ascribed to "rhodium trichloride" refers to the use of the hydrated form. Some procedures calling for a rhodium chloride imply the use of Na₃RhCl₆. These chlorides are the products of the separation of rhodium from the other platinum group metals.

RhCl₃(H₂O)₃ exists as dark red crystals. It is soluble in water to give reddish solutions. It is used to prepare a variety of complexes, such as with carbon monoxide, alkenes, pyridine, and phosphines. RhCl₃(H₂O)₃ and some of its complexes are useful catalysts for various reactions. For example, the complex with phosphine (RhCl(PPh₃)₃), well-known as Wilkinson’s catalyst, is used for the hydrogenation and isomerization of alkenes.

Precautions

As a noble metal, rhodium is chemically inert. Its compounds, however, can be reactive and should be considered highly toxic and carcinogenic. For rats, the lethal intake (LD50) of rhodium chloride (RhCl₃) was found to be 12.6 milligrams per kilograms (mg/kg). Rhodium compounds can leave strong stains on human skin. The element is not known to play any biological role in humans.

Symbolism

Rhodium symbolizes wealth and has been used for giving high honors when more commonly used metals such as silver, gold, or platinum are deemed insufficient. In 1979, the Guinness Book of World Records gave Paul McCartney a rhodium-plated disc for being history's all-time best-selling songwriter and recording artist. Guinness has also noted items such as the world's "Most Expensive Pen" or "Most Expensive Board Game" as containing rhodium.

Notes

↑ Tax Free Gold – Precious Metal Prices Index Retrieved December 4, 2007.

References
ISBN links support NWE through referral fees

Canterford, J.H. and R. Colton. 1968. Halides of the Second and Third Row Transition Metals. London: Wiley-Interscience.
Cotton, S.A. 1997. Chemistry of the Precious Metals. Chapman and Hall. ISBN 0-7514-0413-6
Greenwood, N.N. and Earnshaw, A. 1998. Chemistry of the Elements, 2nd Edition. Oxford, U.K.; Burlington, Massachusetts: Butterworth-Heinemann, Elsevier Science. ISBN 0750633654
Rhodium Los Alamos National Laboratory. Retrieved December 4, 2007.
Rhodium WebElements.com. Retrieved December 4, 2007.

External links

All links retrieved December 8, 2022.

Credits

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[1] Tax Free Gold – Precious Metal Prices Index Retrieved December 4, 2007.

[1]

@@ Line 1: / Line 1: @@
-''[[Rh]] redirects here. For other uses, see [[rh (disambiguation)]]''
+{{Copyedited}}{{Paid}}{{Images OK}}{{Submitted}}{{Approved}}
 {{Elementbox_header | number=45 | symbol=Rh | name=rhodium | left=[[ruthenium]] | right=[[palladium]] | above=[[cobalt|Co]] | below=[[iridium|Ir]] | color1=#ffc0c0 | color2=black }}
 {{Elementbox_series | [[transition metal]]s }}
@@ Line 71: / Line 71: @@
 {{Elementbox_footer | color1=#ffc0c0 | color2=black }}
-'''Rhodium''' ([[International Phonetic Alphabet|IPA]]: {{IPA|/ˈrəʊdiəm/}}) is a [[chemical element]] in the [[periodic table]] that has the symbol '''Rh''' and [[atomic number]] 45. A rare silvery-white hard [[transition metal]], rhodium is a member of the [[platinum group]], is found in platinum ores and is used in [[alloy]]s with platinum and as a [[catalyst]]. It is the most expensive [[precious metal]].[http://www.taxfreegold.co.uk/preciousmetalpricesindx.html]
+'''Rhodium''' (chemical symbol '''Rh''', [[atomic number]] 45) is a rare, silvery-white, inert [[metal]]. It is a member of the [[platinum]] group of elements and is found in platinum ores. As the most expensive [[precious metal]],<ref>[http://www.taxfreegold.co.uk/preciousmetalpricesindx.html Tax Free Gold &ndash; Precious Metal Prices Index] Retrieved December 4, 2007.</ref> it is a symbol of wealth and is occasionally used in the presentation of high honors.
+{{toc}}
+This metal is a hardening agent for the production of durable, heat-resistant [[alloy]]s with platinum and [[palladium]]. These alloys can be found in such items as furnace windings, thermocouple elements, [[aircraft]] [[spark plug]]s, and laboratory crucibles. Rhodium is also good for making electrical contacts, and it is a valuable [[catalyst]] for automobile catalytic converters and various industrial processes. As a highly reflective metal, it provides a good finish for [[jewelry]], mirrors, and searchlights.
+== Occurrence ==
+Rhodium occurs in small amounts in ores of other metals such as [[platinum]], [[palladium]], [[nickel]], [[silver]], and [[gold]]. Its industrial extraction and purification processes are therefore complex. Principal sources of this element are located in [[South Africa]], [[Russia]] (river sands of the [[Ural Mountains]]), and some parts of [[North America|North]] and [[South America]]. In [[Canada]], it is extracted from the [[copper]]-nickel sulfide mining area of the [[Sudbury, Ontario]] region. Although the quantity at Sudbury is very small, the large amount of nickel ore processed makes rhodium recovery cost-effective. The main exporter of rhodium is South Africa, followed by Russia.
+Rhodium can also be extracted from spent nuclear fuel, which contains an average of 400 grams of rhodium per metric ton. Rhodium from this source contains radioactive isotopes with half-lives of up to 2.9 years. In other words, after every 2.9 years, the radioactivity drops by 50 percent. It is therefore stored for at least 20 years in a secure area, to allow it to become stable.
+== Discovery ==
+Rhodium ([[Greek language|Greek]] ''rhodon'', meaning "rose") was discovered in 1803 by [[William Hyde Wollaston]], soon after he discovered [[palladium]]. Wollaston made this discovery in [[England]] using crude [[platinum]] ore that presumably came from [[South America]]. After performing a series of chemical reactions to extract platinum and palladium from the ore, he obtained a red powder of sodium rhodium chloride (Na<sub>3</sub>RhCl<sub>6</sub>.12H<sub>2</sub>O). He then isolated rhodium metal from the powder by reacting it with [[hydrogen]] gas.
 == Notable characteristics ==
-Rhodium is a hard silvery white and durable metal that has a high reflectance. If slowly cooled from a red hot state it changes in air to the [[sesquioxide]], which at higher temperatures  converts back to the metal. Rhodium has both a higher [[melting point]] and lower density than [[platinum]].  It is not attacked by [[acid]]s and only dissolves in [[aqua regia]].
+[[Image:Rhodium_foil_and_wire.jpg|left|thumb|Rhodium foil and wire]]
+Rhodium is classified as a [[transition metal]]. In the [[periodic table]], it lies in period five between [[ruthenium]] and [[palladium]] and is closely related to the latter two elements. In addition, it is situated in group nine (former group 8B), between [[cobalt]] and [[iridium]].
+This hard, silvery metal is highly reflective and extremely resistant to corrosion. It has a higher [[melting point]] and lower density than [[platinum]]. It is not attacked by most [[acid]]s and dissolves only in [[aqua regia]] (a mixture of concentrated [[hydrochloric acid]] and [[nitric acid]] in the ratio 3:1 by volume). If slowly cooled from a red-hot state in the presence of air, rhodium changes to the [[sesquioxide]], and the latter converts back to the metal at higher [[temperature]]s.
+=== Isotopes ===
+Naturally occurring rhodium is composed of only one [[isotope]], <sup>103</sup>Rh, which is stable. In addition, many radioactive isotopes, ranging in mass numbers from 89 to 122, have been produced artificially. Of these, the [[radioisotope]]s with the longest half-lives are: <sup>101</sup>Rh, with a [[half-life]] of 3.3 years; <sup>102</sup>Rh, with a half-life of 2.9 years; <sup>102m</sup>Rh, with a half-life of 207 days; and <sup>99</sup>Rh, with a half-life of 16.1 days.
 == Applications ==
-The primary use of this element is as an alloying agent for hardening [[platinum]] and [[palladium]]. These alloys are used in furnace windings, bushings for glass fiber production, thermocouple elements, [[electrode]]s for aircraft [[spark plug]]s, and laboratory crucibles. Other uses include:
-*It is used as an electrical contact material due to its low electrical resistance, low and stable contact resistance, and its high [[corrosion]] resistance.
-*Plated rhodium, made by [[electroplating]] or evaporation, is extremely hard and is used for optical instruments.
-*This metal finds use in [[jewelry]] and for decorations. It is electroplated on white gold to give it a reflective white surface. This is known as rhodium flashing in the jewelry business.
-*It is also a highly useful [[catalyst]] in a number of industrial processes (notably it is used in the catalytic system of automobile [[catalytic converter]]s and for catalytic carbonylation of methanol to produce [[acetic acid]] by the [[Monsanto process]]). It is used to catalyse addition of hydrosilanes to a double bond, a process important in manufacture of certain silicone rubbers.
-*The complex of a rhodium ion with [[BINAP]] gives a widely used chiral catalyst for [[chiral synthesis]], as in the synthesis of [[menthol]].
-== History ==
+* The primary use of rhodium is as an alloying agent for hardening [[platinum]] and [[palladium]]. These alloys are used in furnace windings, bushings for glass fiber production, thermocouple elements, [[aircraft]] turbine engines and [[spark plug]]s, and laboratory crucibles.
-Rhodium ([[Greek language|Greek]] ''rhodon'' meaning "rose") was [[discovery of the chemical elements|discovered]] in [[1803]] by [[William Hyde Wollaston]] soon after his discovery of [[palladium]]. Wollaston made this discovery in [[England]] using crude [[platinum]] ore that he presumably obtained from [[South America]].
+* Rhodium is also used as an electrical contact material due to its low electrical resistance, low and stable contact resistance, and its high [[corrosion]] resistance.
+* Plated rhodium, made by [[electroplating]] or evaporation, is extremely hard and is used for optical instruments.
+* Given its highly reflective nature, this metal is used as a finish for [[jewelry]], decorative items, mirrors, and search lights.
+* Rhodium is an important [[catalyst]] in automobile [[catalytic converter]]s and a number of industrial processes (such as the manufacture of [[acetic acid]] from methanol). It also catalyzes a process (addition of hydrosilanes to a double bond) used for the manufacture of certain silicone rubbers.
+* The complex of a rhodium ion with the organic compound called “BINAP” gives a widely used catalyst for certain organic chemical syntheses.
-His procedure involved dissolving the ore in [[aqua regia]], neutralizing the acid with [[sodium hydroxide]] ([[sodium|Na]][[oxygen|O]][[hydrogen|H]]). He then precipitated the platinum metal by adding  [[ammonium chloride]], [[nitrogen|N]]H<sub>4</sub>[[chlorine|Cl]], as [[ammonium chloroplatinate]]. The element palladium was removed as [[palladium cyanide]] after treating the solution with [[mercuric cyanide]]. The material that remained was a red [[rhodium(III) chloride]]: rhodium metal was isolated via reduction with [[hydrogen]] gas.
+== Chlorides of rhodium ==
-== Occurrence ==
+The name ''rhodium(III) chloride'' usually refers to ''hydrated rhodium trichloride'', a molecular compound with the formula RhCl<sub>3</sub>(H<sub>2</sub>O)<sub>3</sub>. Another prominent rhodium chloride is RhCl<sub>3</sub>, a polymeric solid that behaves quite differently. Most chemistry ascribed to "rhodium trichloride" refers to the use of the hydrated form. Some procedures calling for a rhodium chloride imply the use of Na<sub>3</sub>RhCl<sub>6</sub>. These chlorides are the products of the separation of rhodium from the other [[Platinum group|platinum group metals]].
-The industrial extraction of rhodium is complex as the metal occurs in ores mixed with other metals such as [[palladium]], [[silver]], [[platinum]], and [[gold]]. It is found in platinum ores and obtained free as a white inert metal which it is very difficult to fuse. Principal sources of this element are located in South Africa, in river sands of the [[Ural Mountains]], in North and South America and also in the [[copper]]-[[nickel sulfide]] mining area of the [[Sudbury, Ontario]] region. Although the quantity at Sudbury is very small, the large amount of nickel ore processed makes rhodium recovery cost effective. The main exporter of rhodium is South Africa (>80%) followed by Russia. However, the annual world production of this element is only about 20 [[ton]]s and there are very few rhodium [[mineral]]s. Moreover, it is generally  difficult to determine if a rock sample does or does not contain platinum group elements. As of 2006, rhodium cost approximately six times as much as gold, by weight.
+RhCl<sub>3</sub>(H<sub>2</sub>O)<sub>3</sub> exists as dark red [[crystal]]s. It is soluble in water to give reddish solutions. It is used to prepare a variety of [[Complex (chemistry)|complexes]], such as with carbon monoxide, alkenes, pyridine, and phosphines. RhCl<sub>3</sub>(H<sub>2</sub>O)<sub>3</sub> and some of its complexes are useful catalysts for various reactions. For example, the complex with phosphine (RhCl(PPh<sub>3</sub>)<sub>3</sub>), well-known as Wilkinson’s catalyst, is used for the [[hydrogenation]] and isomerization of alkenes.
+== Precautions ==
-It is also possible to extract Rhodium from spent nuclear fuel, which contains an average of 400 g of Rhodium per metric ton. Rhodium produced in such a way contains radioactive isotopes with half-lives of up to 2.9 years and is therefore stored at least 20 years in a secured area to allow it to become stable. Every 2.9 years of isolation reduces the radioactivity by 50%. Fission Rhodium has a specific activity of 8.1 curies of radioactivity per gram after 5 years isolation. Under health physics safety rules any isotope that emits more than 1 ci of activity is a hazard however after 8 years the activity falls to 4.1 ci, after 11 years it is 2.2, after 14 years 1.1, after 17 years .55 ci and after 20 years only .27 ci. After 30 years the activity falls to 2.702E-4 ci, which is under the threshold for low level risk by even the most stringent health physics rules.  The radioactivity of Rhodium falls off so quickly because the percentage of Rh-102 in the recovered Rhodium is only a trace amount and the remainder of the material absorbs the energy released.
+As a [[noble metal]], rhodium is chemically inert. Its compounds, however, can be reactive and should be considered highly [[toxic]] and [[carcinogen]]ic. For rats, the lethal intake (LD50) of rhodium chloride (RhCl<sub>3</sub>) was found to be 12.6 milligrams per kilograms (mg/kg). Rhodium compounds can leave strong stains on human skin. The element is not known to play any biological role in humans.
-Rhodium averaged $26.43 per gram or $1000 per troy ounce over the last 30 years and $6200 per troy ounce in May 2006, adding significantly to the resource value of reprocessed fission waste.
-== Isotopes ==
+== Symbolism ==
-Naturally occurring rhodium is composed of only one [[isotope]], <sup>103</sup>Rh. The most stable [[radioisotope]]s are <sup>101</sup>Rh with a [[half-life]] of 3.3 years, <sup>102m</sup>Rh with a [[half-life]] of 207 days, <sup>102</sup>Rh with a [[half-life]] of 2.9 years, and <sup>99</sup>Rh with a half-life of 16.1 days. Twenty other radioisotopes have been characterized with [[atomic weight]]s ranging from 92.926 [[atomic mass unit|u]] (<sup>93</sup>Rh) to 116.925 u (<sup>117</sup>Rh). Most of these have half-lifes that are less than an hour except <sup>100</sup>Rh (half-life: 20.8 hours)  and <sup>105</sup>Rh (half-life: 35.36 hours). There are also numerous [[meta state]]s with the most stable being <sup>102m</sup>Rh (0.141 MeV) with a half-life of about 207 days and <sup>101m</sup>Rh (0.157 MeV) with a half-life of 4.34 days.
-The primary [[decay mode]] before the only stable isotope, <sup>103</sup>Rh, is [[electron capture]] and the primary mode after is [[beta emission]]. The primary [[decay product]] before <sup>103</sup>Rh is [[ruthenium]] and the primary product after is [[palladium]].
+Rhodium symbolizes wealth and has been used for giving high honors when more commonly used metals such as [[silver]], [[gold]], or [[platinum]] are deemed insufficient. In 1979, the Guinness Book of World Records gave [[Paul McCartney]] a rhodium-plated disc for being history's all-time best-selling songwriter and recording artist. Guinness has also noted items such as the world's "Most Expensive Pen" or "Most Expensive Board Game" as containing rhodium.
-== Precautions ==
+== See also ==
-Rhodium metal is, as a [[noble metal]], inert.
-However, when rhodium is chemically bound, it is reactive. Rhodium compounds are not often encountered by most people and should be considered to be highly [[toxic]] and [[carcinogen]]ic. Lethal intake (LD50) for rats is 12.6 mg/kg of rhodium chloride (RhCl<sub>3</sub>). Rhodium compounds can stain human skin very strongly. This element plays no biological role in humans.
+* [[Chemical element]]
+* [[Metal]]
+* [[Periodic table]]
+* [[Transition metal]]
-== Symbolic uses ==
+== Notes ==
-Rhodium has been used for honours, or to symbolize wealth, when more commonly used metals such as silver, gold, or platinum are deemed insufficient.  In 1979 the Guinness Book of World Records gave [[Paul McCartney]] a rhodium-plated disc for being history's all-time best-selling songwriter and recording artist.  Guinness has also noted items such as the world's "Most Expensive Pen" or "Most Expensive Board Game" as containing rhodium
+<references/>
 ==References==
-*[http://periodic.lanl.gov/elements/45.html Los Alamos National Laboratory &ndash; Rhodium]
+* Canterford, J.H. and R. Colton. 1968. ''Halides of the Second and Third Row Transition Metals''. London: Wiley-Interscience.
+* Cotton, S.A. 1997. ''Chemistry of the Precious Metals''. Chapman and Hall. ISBN 0-7514-0413-6
+* Greenwood, N.N. and Earnshaw, A. 1998. ''Chemistry of the Elements'', 2nd Edition. Oxford, U.K.; Burlington, Massachusetts: Butterworth-Heinemann, Elsevier Science. ISBN 0750633654
+*[http://periodic.lanl.gov/elements/45.html Rhodium] Los Alamos National Laboratory. Retrieved December 4, 2007.
+*[http://www.webelements.com/webelements/elements/text/Rh/index.html Rhodium] WebElements.com. Retrieved December 4, 2007.
 == External links ==
-*[http://www.webelements.com/webelements/elements/text/Rh/index.html WebElements.com &ndash; Rhodium]
+All links retrieved December 8, 2022.
 *[http://www.kitco.com/charts/rhodium.html Kitco Rhodium prices]
+*[http://environmentalchemistry.com/yogi/periodic/Rh.html#Chemical EnvironmentalChemistry.com &ndash; Rhodium]
-[[Image:Rhodium_foil_and_wire.jpg|left|thumb|Rhodium foil and wire]]
+* [http://www.lenntech.com/Periodic-chart-elements/Rh-en.htm#Health%20effects%20of%20rhodium Lenntech &ndash; Rhodium]
-{{Commons|Rhodium}}
-{{wiktionary|rhodium}}
-[[Category:Rhodium| ]]
+[[Category:Physical sciences]]
+[[Category:Chemistry]]
+[[Category:Earth sciences]]
 [[Category:Chemical elements]]
-[[Category:Transition metals]]
-[[ar:روديوم]]
+{{credit2|Rhodium|82394233|Rhodium(III)_chloride|72734188}}
-[[ca:Rodi]]
-[[cs:Rhodium]]
-[[co:Rodiu]]
-[[da:Rhodium]]
-[[de:Rhodium]]
-[[et:Roodium]]
-[[el:Ρόδιο]]
-[[es:Rodio]]
-[[eo:Rodio]]
-[[fr:Rhodium]]
-[[ko:로듐]]
-[[hr:Rodij]]
-[[io:Rodio]]
-[[id:Rhodium]]
-[[is:Ródín]]
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-[[no:Rhodium]]
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-[[oc:Ròdi]]
-[[ug:رودىي]]
-[[pl:Rod (pierwiastek)]]
-[[pt:Ródio]]
-[[ru:Родий]]
-[[sl:Rodij]]
-[[sr:Родијум]]
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-[[fi:Rodium]]
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-[[th:โรเดียม]]
-[[uk:Родій]]
-[[uz:Rodiy]]
-[[zh:铑]]