Periodic System for Chemists
Table
75
186.21

Re

Rhenium

Identification

CAS Number: 7440-15-5
Discovery Year: 1925
Discoverer: Walter Noddack, Ida Tacke, Otto Berg
Discovery Location: Germany

Properties

Atomic Mass: 186.207 →Density: 20.8 g/cm³ →
Crust Abundance: 0.0007 mg/kg
Crystal Structure: HEX

Atomic Dimensions

Atomic Radius: 135 pm →
Atomic Radius (Rahm): 249.00000000000003 pm
Covalent Radius: 151 pm →
Van der Waals Radius: 216 pm
Metallic Radius: 128 pm
Atomic Volume: 8.85 cm³/mol
Lattice Constant: 2.76 Å

Thermodynamics

Melting Point: 3453 K →Boiling Point: 5900 K →Specific Heat: 0.138 J/(g·K) →Thermal Conductivity: 48 W/(m·K) →Heat of Fusion: 34 kJ/mol →Heat of Vaporization: 704 kJ/mol →
Heat of Formation: 774 kJ/mol

Electronic Structure

Electron Config: [Xe] 4f14 5d5 6s2
Block: d
Period: 6 →Group: 7 →Electronegativity: 1.9 →Electron Affinity: 0.15 eV →
Oxidation States: -1, +2, +3, +4, +5

Abundance & Geochemistry

Crust Abundance: 0.0007 mg/kg
Sea Abundance: 0.000004 mg/L
Goldschmidt Class: siderophile

About

Silvery-white metallic transition element. Obtained as a by-product of molybdenum refinement. Rhenium-molybdenum alloys are superconducting.

Isotopes

Re-187 187 62.60%
Re-185 185 37.40%