Rhenium

75
Re
Group
7
Period
6
Block
d
Protons
Electrons
Neutrons
75
75
111
General Properties
Atomic Number
75
Atomic Weight
186.207
Mass Number
186
Category
Transition metals
Color
Gray
Radioactive
No
From the Latin word Rhenus meaning Rhine
Crystal Structure
Simple Hexagonal
History
In 1908, Japanese chemist Masataka Ogawa announced that he discovered the 43rd element.

However, later analysis indicated the presence of rhenium (element 75), not element 43.

In 1922, Walter Noddack, Ida Eva Tacke and Otto Berg announced its separation from gadolinite and gave it the present name.
Electrons per shell
2, 8, 18, 32, 13, 2
Electron Configuration
[Xe] 4f14 5d5 6s2
Re
Chile has the world's largest rhenium reserves
Physical Properties
Phase
Solid
Density
21.02 g/cm3
Melting Point
3459.15 K | 3186 °C | 5766.8 °F
Boiling Point
5869.15 K | 5596 °C | 10104.8 °F
Heat of Fusion
33 kJ/mol
Heat of Vaporization
705 kJ/mol
Specific Heat Capacity
0.137 J/g·K
Abundance in Earth's crust
2.6×10-7%
Abundance in Universe
2×10-8%
A
Image Credits: Wikimedia Commons (Alchemist-hp)
A high purity rhenium single crystal made by the floating zone process, an ebeam remelted rhenium bar and as well as a high purity rhenium cube for comparison
CAS Number
7440-15-5
PubChem CID Number
23947
Atomic Properties
Atomic Radius
137 pm
Covalent Radius
151 pm
Electronegativity
1.9 (Pauling scale)
Ionization Potential
7.8335 eV
Atomic Volume
8.85 cm3/mol
Thermal Conductivity
0.479 W/cm·K
Oxidation States
-3, -1, 1, 2, 3, 4, 5, 6, 7
Applications
Rhenium is widely used as filaments for mass spectrographs and ion gauges.

It is also used with platinum as catalysts in the production of lead-free, high-octane gasoline.

Nickel-based superalloys of rhenium are used in the combustion chambers, turbine blades, and exhaust nozzles of jet engines.
Very little is known about the toxicity of rhenium
Isotopes
Stable Isotopes
185Re
Unstable Isotopes
160Re, 161Re, 162Re, 163Re, 164Re, 165Re, 166Re, 167Re, 168Re, 169Re, 170Re, 171Re, 172Re, 173Re, 174Re, 175Re, 176Re, 177Re, 178Re, 179Re, 180Re, 181Re, 182Re, 183Re, 184Re, 186Re, 187Re, 188Re, 189Re, 190Re, 191Re, 192Re, 193Re, 194Re