Rh
102.910Rhodium
Rodyum
Rhodium is a rare platinum-group metal with atomic number 45. It is best known for catalytic converters, NOx reduction, rhodium plating, high-temperature thermocouples and homogeneous catalysts such as Wilkinson’s catalyst.
45
102.91 g/mol
[Kr] 4d⁸ 5s¹
2 | 8 | 18 | 16 | 1
2.28
12.41 g/cm³
1963.8 °C
3694.8 °C
William Hyde Wollaston
Rhodium was discovered in 1803 by William Hyde Wollaston while studying crude platinum ores. It was named from the Greek rhodon, meaning rose, because some rhodium salts have a rose-red color.
Rhodium-103
Natural abundance: 100%. The only stable naturally occurring isotope of rhodium.RhCl₃
Rhodium(III) ChlorideCatalyst precursor and rhodium plating chemistry.Rh₂O₃
Rhodium(III) OxideCatalysis and specialty material research.RhCl(PPh₃)₃
Wilkinson’s CatalystHomogeneous catalyst for alkene hydrogenation.- Three-way catalytic converters, especially for reducing nitrogen oxides
- Rhodium plating on white gold, silver jewelry and reflective surfaces
- Platinum-rhodium thermocouples for high-temperature measurement
- Homogeneous catalysts such as Wilkinson’s catalyst
- Electrical contacts and corrosion-resistant coatings
Rhodium has no known essential biological role.
- Rhodium is often one of the most expensive precious metals because production is limited and demand from catalytic converters is high.
- Most rhodium use is tied to automotive emission control.
- Rhodium-103 makes natural rhodium monoisotopic.
- Rhodium plating gives jewelry a bright, reflective, corrosion-resistant finish.
- Rhodium has atomic number 45 and belongs to group 9.
- Its electron configuration is [Kr] 4d⁸ 5s¹.
- Rhodium is a platinum-group metal and commonly forms Rh³⁺ compounds.
- Catalytic converters use rhodium especially for NOx reduction.
What is the atomic number of rhodium?
The atomic number of rhodium is 45.
What is the electron configuration of rhodium?
Rhodium has the electron configuration [Kr] 4d⁸ 5s¹.
What is rhodium used for?
Rhodium is used in catalytic converters, jewelry plating, thermocouples, catalysts and corrosion-resistant electrical contacts.
Why is rhodium used in catalytic converters?
Rhodium is especially effective for reducing nitrogen oxides in vehicle exhaust.
Is rhodium monoisotopic?
Yes. Natural rhodium consists essentially of stable rhodium-103.
What is Wilkinson’s catalyst?
Wilkinson’s catalyst is a rhodium complex used for homogeneous hydrogenation of alkenes.