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Rhenium (Re)

Rhenium is a chemical element of the periodic table with chemical symbol Re and atomic number 75 with an atomic weight of 186.207 u and is classed as transition metal and is part of group 7 (manganese group). Rhenium is solid at room temperature.

Rhenium in the periodic table

Atomic number75
Group7 (Manganese group)
ClassificationTransition Metal
Color Gray
Number of protons75 p+
Number of neutrons111 n0
Number of electrons75 e-
From Wikipedia, the free encyclopediaRhenium is a chemical element with symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust.

Physical properties

Phase at STPSolid
Density21.02 g/cm3
Atomic weight186.207 u

Thermal properties

Melting point3459 K
3185.85 °C
5766.53 °F
Boiling point5869 K
5595.85 °C
10104.53 °F
Heat of vaporization707.1 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)1.9
Electron affinity5.8273 kJ/mol
Oxidation states−3, −1, 0, +1, +2, +3, +4, +5, +6, +7
(a mildly acidic oxide)
Ionization energies
  1. 760 kJ/mol
  2. 1260 kJ/mol
  3. 2510 kJ/mol
  4. 3640 kJ/mol

Electron configuration for rhenium

Electron configuration
Shorthand configuration
[Xe] 4f14 5d5 6s2
Electron configuration
Full configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d5 6s2
Electron configuration chart
Electrons per shell2, 8, 18, 32, 13, 2
Valence electrons 2
Valency electrons 7
Bohr model
RheniumElectron shell for Rhenium, created by Injosoft ABRe
Figure: Shell diagram of Rhenium (Re) atom.
Orbital Diagram

The history of Rhenium

DiscoveryWalter Noddack, Ida Noddack, Otto Berg (1925)
First isolationWalter Noddack, Ida Noddack (1928)
Discovery of rhenium
In 1922, Walter Noddack and Ida Tacke (future spouses Noddack) began searching for the elements number 43 (technetium) and 75 (rhenium). The Noddacks extracted 1 mg of oxide of what they believed to be element number 75 from platinum ore, and by X-ray emission spectroscopy found lines belonging to element number 75. Then the Noddacks published the discovery of element number 75 and named it rhenium after the river Rhine in Europe.


List of unique identifiers for Rhenium in various chemical registry databases
CAS Number7440-15-5
ChemSpider ID22388
EC number231-124-5
PubChem CID Number23947