Atomic number:75

Group numbers:7

Period:6

Electronic configuration:[Xe] 4f¹⁴ 5d⁵ 6s²

Formal oxidation number:+4 +6 +7

Electronegativities:1.9

Atomic radius / pm:137.1

Relative atomic mass:186.207 ± 0.001

 

Rhenium was discovered by Walter Noddack, Ida Tacke-Noddack and Otto Berg (DE) in 1925. The origin of the name comes from the Latin word Rhenus meaning river Rhine. It is a rare and costly, dense, silvery-white metal that tarnishes in moist air, resists corrosion and oxidation .Rhenium dissolves in nitric and sulfuric acids but has a very high melting point. Rhenium is found in small amounts in gadolinite and molybdenite. It is mixed with tungsten or platinum to make filaments for mass spectrographs. Its main value is as a trace alloying agent for hardening metal components that are subjected to continuous frictional forces.

Density / g dm^-3:21020 (293 K)

 18900 (m.p.)

Molar volume / cm³mol^-1:8.86 (293 K)

 9.85 (m.p.)

Electrical resistivity / μΩcm:19.3 (20 °C)

Thermal conductivity / W m^-1K^-1:47.9

Melting point / °C:3186

Boiling point / °C:5596

Heat of fusion / kJ mol^-1:33.1

Heat of vaporization / kJ mol^-1:704.25

Heat of atomization / kJ mol^-1:769

1st ionization energy / kJ mol^-1:755.82

2nd ionization energy / kJ mol^-1:-

3rd ionization energy / kJ mol^-1:-

in the atmosphere / ppm:-

in the Earth's crust / ppm:0.0005

in the oceans / ppm:1E-10