75 Re 186.21

Rhenium

Transition metal · Group 7 · Period 6

Rhenium (symbol Re, atomic number 75) is one of the rarest metals, used in jet-engine superalloys. It is classified as a transition metal and sits in group 7, period 6 of the periodic table.

Overview

Rhenium is the chemical element with atomic number 75 and the symbol Re. With a standard atomic weight of 186.21, it is a transition metal. In the periodic table it occupies group 7 and period 6, and under standard conditions it is normally a solid. Rhenium is one of the rarest metals, used in jet-engine superalloys.

Atomic structure

An atom of Rhenium has 75 protons in its nucleus and, when neutral, 75 electrons arranged in the configuration [Xe] 4f14 5d5 6s2. Its standard atomic weight of 186.21 reflects the natural mix of its stable isotopes.

Discovery and place in the table

Rhenium was discovered in 1925 by Walter Noddack, Ida Tacke, Otto Berg. It follows Tungsten (W) and precedes Osmium (Os) in order of atomic number.

Key properties of Rhenium
Atomic number 75
Symbol Re
Atomic mass 186.21
Category Transition metal
Group 7
Period 6
Electron configuration [Xe] 4f14 5d5 6s2
Phase at STP Solid
Discovered 1925 (Walter Noddack, Ida Tacke, Otto Berg)