075Transition metal · Group 7 · Period 6

Rhenium

Rhenium (Re) is element 75, a transition metal in the d-block — group 7, period 6. It is a solid at room temperature with 6 electron shells (2, 8, 18, 32, 13, 2) and an atomic mass of 186.2071 u.

Atomic mass: 186.2 u
Phase · STP: solid
Melting: 3459 K · 3186 °C
Boiling: 5869 K · 5596 °C
Electronegativity: 1.9
Density: 21.02 g/cm³

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Identity

Atomic number: 75
Standard atomic weight: 186.2 u
Category: Transition metal
Group: 7
Period: 6
Block: d-block
Oxidation states: +7, +6, +4

Physical properties

Melting point: 3459 K · 3186 °C
Boiling point: 5869 K · 5596 °C
Density: 21.02 g/cm³
Molar heat capacity: 25.48 J/(mol·K)
Atomic radius: 217 pm
Electron affinity: 5.8273 kJ/mol

Atomic structure

75protons

111neutrons

75electrons

2valence e⁻

Noble-gas notation: [Xe] 4f14 5d5 6s2
Full configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d5
Electrons per shell: 2, 8, 18, 32, 13, 2

Periodic trends

Where Rhenium ranks across all 118 elements.

Electronegativity1.9

Ionization energy760 kJ/mol

Electron affinity5.8273 kJ/mol

Density21.02 g/cm³

Atomic radius217 pm

Ionization energies

Energy to remove each successive electron (kJ/mol).

760

1.3k

2.5k

3.6k

Successive ionization energies (kJ/mol, log scale).

Discovery

Discovered: 1925
Discovered by: Masataka Ogawa
Named by: Walter Noddack
Appearance: silvery-grayish