ElementsWhat is rhenium?
Rhenium is a silvery-white metal with a very high melting point. It is one of the rarest elements in the Earth's crust.
What is rhenium used for?
Alloys for the hottest parts of jet engines, and catalysts for making lead-free, high-octane petrol.
Where the name comes from
From Rhenus, the Latin name for the river Rhine.
Key facts
- Symbol
- Re
- Atomic number
- 75
- Atomic mass
- 186.207 u
- Family
- Transition metal
- Period
- 6
- Group
- 7
- Block
- d
- State at room temperature
- Solid
- Melting point
- 3,186 °C (3,459 K, 5,767 °F)
- Boiling point
- 5,596 °C (5,869 K, 10,105 °F)
- Density
- 20.8 g/cm³
- Electrons per shell
- 2, 8, 18, 32, 13, 2
- Electron configuration
- [Xe]6s2 4f14 5d5
- Common oxidation states
- +7, +6, +4
- Electronegativity (Pauling)
- 1.9
- First ionisation energy
- 7.88 eV
- Electron affinity
- 0.15 eV
- Atomic radius (van der Waals)
- 217 pm
- Discovered
- 1925
Place in the periodic table
Rhenium is element number 75. It sits in period 6 (row 6) of the periodic table, in group 7 (column 7), and belongs to the d-block. Just before it comes tungsten (74), and just after it comes osmium (76). In the same column, technetium is above it and bohrium is below it. Elements in one column tend to behave alike.
Family: Transition metals.
Physical properties
At room temperature rhenium is a solid. It melts at 3,186 °C and boils at 5,596 °C, so it stays liquid over a range of 2,410 degrees. Its density is 20.8 grams per cubic centimetre, so a one-litre block would weigh about 20.8 kilograms. By density it ranks 4th among the 96 elements with a measured value. It has the 3rd highest melting point of all elements.
Inside the atom
An atom of rhenium has 75 protons in its nucleus and, when neutral, 75 electrons around it. The electrons are arranged in 6 shells: 2, 8, 18, 32, 13, 2. The outermost shell holds 2 electrons. Written in full, the electron configuration is [Xe]6s2 4f14 5d5.
Its electronegativity on the Pauling scale is 1.9. This number shows how strongly an atom pulls shared electrons towards itself: fluorine, the strongest, is 3.98. Removing one electron from an atom takes 7.88 electronvolts (about 760 kilojoules per mole). One mole of rhenium weighs 186.207 grams, so a single gram contains about 3.23 × 1021 atoms.
The ring picture is a simple model that only counts the electrons in each shell. Real atoms do not look like this.
Next steps
- Work out the weight of a compound that contains rhenium with the molar mass calculator.
- Compare it with every other element in the sortable list.
- Test yourself with the symbol quiz.
Figures on this page are from PubChem (U.S. National Library of Medicine), as downloaded on 11 November 2026. See About and data sources.