Rh

Rhodium

Identification

CAS Number: 7440-16-6

Discovery Year: 1803

Discoverer: William Wollaston

Discovery Location: England

Properties

Atomic Mass: 102.9055 →Density: 12.4 g/cm³ →

Crust Abundance: 0.001 mg/kg

Crystal Structure: FCC

Atomic Dimensions

Atomic Radius: 135 pm →

Atomic Radius (Rahm): 233 pm

Covalent Radius: 142 pm →

Van der Waals Radius: 210 pm

Metallic Radius: 125 pm

Atomic Volume: 8.3 cm³/mol

Lattice Constant: 3.8 Å

Thermodynamics

Melting Point: 2239 K →Boiling Point: 4000 K →Specific Heat: 0.244 J/(g·K) →Thermal Conductivity: 150 W/(m·K) →Heat of Fusion: 21.8 kJ/mol →Heat of Vaporization: 494 kJ/mol →

Heat of Formation: 556 kJ/mol

Electronic Structure

Electron Config: [Kr] 4d8 5s

Block: d

Period: 5 →Group: 9 →Electronegativity: 2.28 →Electron Affinity: 1.137 eV →

Oxidation States: +1, +2, +3, +4, +5

Abundance & Geochemistry

Crust Abundance: 0.001 mg/kg

Geochemical Class: noble metal

Goldschmidt Class: siderophile

About

Silvery white metallic transition element. Found with platinum and used in some platinum alloys. Not attacked by acids, dissolves only in aqua regia. Discovered in 1803 by W.H. Wollaston.

Isotopes

Rh-103 103 100.00%