Symbol: Rh
Date of discovery: 1803
Name origin: Greek rhodon
Appearance: silver-white
Discoverer: William Wollaston
Obtained from: platinum ores
Melting point: 2237 K
Boiling point: 3968 K
Density[kg/m3]: 12450
Molar volume: 8.28 × 10-6 m3/mol
Protons/Electrons: 45
Neutrons: 58
Shell structure: 2,8,18,16,1
Electron configuration: [Kr]4d85s1
Oxidation state: 2,3,4
Crystal structure: cubic
This silvery-white hard transition metal belongs to the platinum group. It has high reflectance and is hard and durable. Rhodium is primarily used as an alloying agent with platinum and iridium to improve high temperature strength and oxidatlion resistance. These metal alloys are employed in furnace windings, electrical contacts, and high temperature resistance wires. As the pure metal, rhodium’s brilliance and resistance to tarnish makes it well suited for plating jewelry. This metal was discovered in 1803 by W. Wollaston and is named from the Greek origin "rhono", meaning rose, after the rosy-colored solution yielded by its salts.